THE UN OFFENSIVE

The Foundation of Freedom is the Courage of Ordinary People

History On Line

Map and Battles of the MLR

Introduction
The Korean War still has much to teach us: about military preparedness, about global strategy, about combined operations in a military alliance facing blatant aggression, and about the courage and perseverance of the individual soldier. The modern world still lives with the consequences of a divided Korea and with a militarily strong, economically weak, and unpredictable North Korea. The Korean War was waged on land, on sea, and in the air over and near the Korean peninsula. It lasted three years, the first of which was a seesaw struggle for control of the peninsula, followed by two years of positional warfare as a backdrop to extended cease-fire negotiations. The following essay is one of five accessible and readable studies designed to enhance understanding of the U.S. Army's role and achievements in the Korean conflict.
The UN Offensive
16 September-2 November 1950
Following a surprise North Korean attack on 25 June 1950, Lt. Gen. Walton H. Walker's Eighth Army fought desperate battles to halt the invasion before finally establishing a defensive line to protect the vital port city of Pusan on the southeast coast of the Korean peninsula. By August the Pusan Perimeter stretched about one hundred miles north along the west bank of the Naktong River, west of Pusan, and, after turning east near Naktong-ni, about fifty miles to the coast above P'ohang-dong. As the fighting ensued along the perimeter, more American forces entered Korea to stem the Communist tide.
From the first days of the Korean attack General of the Army Douglas MacArthur, Commander in Chief, United Nations (UN) Command, perceived that the deeper the North Korean People's Army (NKPA) pushed into South Korea, the more vulnerable it would become to an amphibious envelopment. MacArthur naturally thought in terms of an amphibious landing in the enemy's rear area to win the Korean War. In World War II, after Bataan, all of his campaigns in the Southwest Pacific had begun as amphibious operations. Such operations took advantage of American control of the sea and the enemy's weakness in his rear.
Strategic Setting
Even as the first U.S. Army units arrived in Korea, MacArthur's staff began planning for the amphibious assault behind North Korean lines. The best site was Inch'on, a Yellow Sea port halfway up Korea's west coast. To the east lay the capital city of Seoul, where the main roads and rail lines converged. MacArthur reasoned that a force landing at Inch'on would have to move inland only a short distance to cut the NKPA's main north-south supply routes. A secondary but significant consideration was Seoul's psychological importance as the traditional capital for all of Korea. MacArthur believed a landing at Inch'on, combined with the Eighth Army's northward advance, would blunt the enemy offensive. As a result, the retreating enemy would be either cut off or forced to make a slow and difficult withdrawal through the mountains farther east.
The nature and location of the planned landing dictated that it be directed by a tactical headquarters separate from Eighth Army. To that end, MacArthur created the X Corps headquarters from members of his own staff, naming his chief of staff, Maj. Gen. Edward M. Almond, as corps commander. The X Corps was activated on 26 August 1950 as a separate command under the General Head-quarters, Far East Command.
(BK Comment: In the opinion of many, Almond's appointment was a tragic error. First Marine Division was the steel heart of X Corps, and its veteran Commandant, Maj. Gen. O.P. Smith, would have been far more effective. General Almond's errors might well have lost the Inchon invasion had not Gen. Smith opposed his wish to substitute a mixture of green US and ROK troops for the veteran 5th Marines in the assault. At Seoul, Almond's assault schedule was based on a political timetable for capturing the Capitol, rather than tactically sound objectives, resulting in the extremely high Marine casualties. Even more tragically, Almond chose to ignore the strength of the attacking Chinese "laundrymen" at Chosin, which led to the total destruction of the Army's own 32nd Infantry Regiment. That the entire First Marine Division was not similarly destroyed is largely due to General Smith and his veteran Regimental Commanders following their own judgment wherever honorably possible and exercising sound deployment and coordination of forces. When the Army strategists nonetheless sent 1stMarDiv into an 80,000 man CCF ambush, they saved themselves against all odds, fighting back out together with their wounded and most of their dead and equipment.)

General Almond
(National Archives)
Although pressed in meeting Eighth Army troop requirements, MacArthur was able to shape a two-division landing force, consisting of the 7th Infantry Division and the 1st Marine Division. In Japan, performing occupation duties, the 7th Division had contributed key personnel to the 24th and 25th Infantry and 1st Cavalry Divisions as they loaded out for Korea. MacArthur rebuilt the vastly understrength division by giving it high priority on replacements from the United States and by assigning it eighty-six hundred South Korean recruits, known as KATUSAs, from the Korean Augmentation to the United States Army program. The 1st Marine Division, which MacArthur acquired from the United States, was augmented by the 1st Provisional Marine Brigade from the Pusan Perimeter and by a Republic of Korea (ROK) Marine Corps regiment. With these two divisions, along with artillery, engineer, and other support elements, the X Corps was to make the landing at Inch'on. Except for the ROK 17th Regiment, which was reassigned from the Eighth Army to the X Corps, no reinforcements were available.
Naval officials and MacArthur's superiors judged the Inch'on plan as dangerous. Navy planners considered the Yellow Sea's extreme tidal variations, sometimes as high as thirty feet, and the narrow channel approaches to the port as major risks to shipping. Marine planners saw peril in landing in the middle of a built-up area and in having to scale high seawalls to get ashore. The Joint Chiefs of Staff were concerned that MacArthur was committing his last major reserves at a time when no more units in the United States were available for deployment to the Far East. Four National Guard divisions had been federalized on 1 September, but none was yet ready for combat duty; and while the draft and the call-ups of Organized Reserve Corps members were substantially increasing the size of the Army, they offered MacArthur no prospect of immediate reinforcement. Should the landing run into strong opposition, no help could be expected. But MacArthur was willing to accept the risks. In light of the uncertainties, his decision was a remarkable gamble and, given the results, one of exemplary boldness.
Operations
As D-day for the Inch'on landing approached, General Walker was busy marshaling his forces for the breakout from the Pusan Perimeter. At this time, Walker had under his direct command the 2d and 25th Infantry Divisions and the I Corps. Under the corps' control were the 24th Infantry and 1st Cavalry Divisions; the 5th Regimental Combat Team (RCT), formed from the 5th Infantry; the British 27th Infantry Brigade; and supporting troops. Earlier, on 17 July, MacArthur informed Walker that all ROK ground forces would be placed under his command, pursuant to South Korean President Syngman Rhee's expressed desire.
Walker planned to have I Corps forces break out of the perimeter's center near Waegwan, with the main effort directed northward along the Taegu-Kumch'on-Taejon-Suwon axis. Initially, the 5th Regimental Combat Team and the 1st Cavalry Division would seize a bridgehead over the Naktong River near Waegwan, allowing the 24th Division to drive toward Kumch'on and Taejon. The 1st Cavalry Division would follow, securing the attacking division's rear and lines of communications. Concurrently, the 2d and 25th Divisions on the Eighth Army's left flank and the ROK I and II Corps on the east and right flank would attack and fix enemy troops in their zones, exploiting any local breakthrough.
The plan had some problems. To supplement the 5th RCT's Naktong bridgehead mission, Walker wanted the 2d and 24th Divisions to ford the river below Waegwan and the ROK 1st Division the portion above the town. However, the plan for multiple crossings was fraught with difficulties because the Eighth Army lacked the engineer troops and bridging equipment for simultaneous river assaults. In fact, it had only enough equipment for two ponton treadway bridges across the Naktong.
In addition, Walker was unable to concentrate a large force in the Pusan Perimeter's center for the breakout effort. Attacks by NKPA units had pinned down all of the divisions under Walker's command except the 24th. Only on the eve of the offensive was he able to move that division in increments from the east to the perimeter's center.
Essentially, the Eighth Army offensive constituted more of a holding attack, allowing the X Corps to make the main effort. Walker's forces would then need to link up quickly with the X Corps to cut off a large body of North Koreans in the southwestern part of the peninsula. Walker anticipated that the news of the Inch'on landing would have a demoralizing effect on the North Koreans while boosting the spirits of his troops. For that reason, he requested that the Eighth Army delay its attack until the day after the Inch'on landing.
The Inch'on Landing
The invasion of Inch'on, code-named Operation Chromite, began on the morning of 15 September, the objectives being to capture Inch'on and then to liberate Seoul. The X Corps invasion force, numbering nearly seventy thousand men, arrived off the landing beaches one hundred fifty miles behind enemy lines -- the effort marking the first major amphibious assault by American troops since 1 April 1945 at Okinawa during World War II. The initial phase called for the seizure of the fortified Wolmi Island that protected Inch'on Harbor. The assault force, consisting of the 3d Battalion, 5th Marines, 1st Marine Division, and a platoon of nine M26 tanks from Company A, 1st Marine Tank Battalion, hit the island at 0633 and moved rapidly inland against little resistance. Within a few minutes more troops landed and moved across the island to seal off the causeway leading to Inch'on. The reduction of Wolmi continued systematically and was completed at 0750. Marine casualties were 17 wounded. Enemy losses were 108 soldiers killed and 136 captured. Preinvasion intelligence about Wolmi Island proved accurate. Enemy prisoners indicated that about four hundred soldiers of the 3d Battalion, 226th Independent Marine Regiment, and some artillery troops of the 918th Artillery Regiment had defended the island.
While the initial fighting had gone well, the battle was far from over. After the capture of Wolmi an anxious period prevailed when the tide began to fall, stopping further landing operations until late in the afternoon. Although the North Koreans were now fully alerted, they had few troops in the region. Moreover, American aircraft covered the countryside during the day, isolating the port to a distance of twenty-five miles, and naval gunfire the closer approaches to Inch'on.
Late in the afternoon assault troops of the 1st and 5th Marines headed for separate landing areas, designated Red and Blue Beaches, on the Inch'on shoreline. The 5th Marines' first wave arrived at Red Beach at 1733. Most of the men had to climb the seawall with scaling ladders, although some made their way through holes in the wall created by the naval bombardment. Two objectives, Cemetery and Observatory Hills, lay in front of the assault force. On the left flank of the landing area an intense firefight ensued when a marine platoon encountered North Korean soldiers in trenches and a bunker just beyond the seawall. Nevertheless, Cemetery Hill was taken just twenty-two minutes after the landing, with many of its defenders throwing down their weapons and surrendering. By midnight other marine elements had fought their way against sporadic resistance to the top of Observatory Hill. Meanwhile, the 1st Marines' first wave reached Blue Beach at 1732, and most of the men also had to climb a high seawall that fronted the area. Fighting through the evening and into the night, the assault force had taken its final D-day objectives by 0130, 16 September. Marine casualties were 20 men killed, 174 wounded, and 1 missing in action.
The Inch'on landing had come as a complete surprise to the North Koreans. Consistent with preinvasion estimates, enemy prisoners related that the Inch'on garrison consisted of about two thousand men. As garrison reinforcements, elements of the 22d Regiment had moved to Inch'on before dawn on the fifteenth but retreated to Seoul after the main landing that evening. Prepared defenses had been minimal and resistance uncoordinated.
By the morning of 16 September the 1st and 5th Marines had joined forces and were advancing rapidly against light resistance. By evening they had reached a prearranged beachhead line, six miles inland from the actual landing area. The line, which included the port as well as the high ground east of Inch'on, was deep enough to prevent enemy artillery fire on the landing and unloading areas, and served as a base to seize Kimp'o Airfield, the next objective, about halfway between Inch'on and Seoul. The 5th Marines reached the edge of the airfield by 1800 on 17 September, taking the southern part within the next two hours. The airfield's four hundred to five hundred defenders appeared surprised and were easily brushed aside. Several company-size counterattacks struck the airfield's perimeter positions during the night, but the North Koreans were repulsed, suffering heavy casualties and finally fleeing to the northwest. The Americans secured the airfield during the morning of 18 September. As a result, the United Nations Command gained its first ground air base north of the Pusan region, which greatly eased its ability to support not only the attack on Seoul but also interdiction operations throughout South Korea.
By now, the remaining X Corps elements had arrived to join in the battle for Seoul. Ships carrying the 7th Division from Japan reached Inch'on Harbor on 16 September. General Almond wanted the troops disembarked as soon as possible to cover the area south of Seoul from any North Korean units that might have been sent north from the Pusan region. The 7th Division's 2d Battalion, 32d Infantry, landed during the morning of the eighteenth; the remainder of the regiment went ashore later in the day. The next morning the 2d Battalion moved up to relieve the 1st Marine Division's 2d Battalion, 1st Marines, which was occupying positions on the right flank south of the Seoul highway. Meanwhile, the 7th Division's 31st Infantry came ashore at Inch'on. Responsibility for the zone south of the Seoul highway passed to the 7th Division at 1800, 19 September.
The Battle for Seoul
With Inch'on and its harbor secured, the X Corps now faced the daunting task of retaking Seoul itself. Seoul, twenty-five miles to the east, had been reinforced after the Inch'on landings and now held over twenty thousand NKPA soldiers. Protecting Seoul to the south and southwest was the wide Han River. The city was heavily damaged and presented a formidable obstacle, with numerous street barricades and enemy positions on the hills dominating its approaches. The assault on the city would be aided somewhat by the recapture of Kimp'o Airfield and its subsequent use by American close air support aircraft. But indications were that the battle for the city would be far greater than had been the action at Inch'on and the advance to the Han River.
As the 1st Marines fought its way east along the Inch'on-Seoul highway into Yongdungp'o, about one and a half miles west of Seoul on the south side of the Han River, the 7th Division protected the marines' right flank and engaged enemy forces moving toward the battle area from the south. Seeking to cut the Seoul-Suwon highway, the 32d Infantry attacked southeast toward Anyang-ni, about five miles south of Yongdungp'o, until 20 September, when its advance was halted by an extensive minefield. Exploding mines damaged three tanks of Company A, 73d Tank Battalion, completely blocking the narrow dirt road the column was following. After engineer troops removed more than one hundred fifty mines, the 32d Infantry resumed its advance toward Anyang-ni, capturing Tongdok Mountain and part of Copper Mine Hill.
The 32d Infantry took the rest of Copper Mine Hill the following day, 21 September, and captured the high ground northeast of Anyang-ni. When night fell, its 3d Battalion held blocking positions astride the Suwon highway, two miles south of Anyang-ni, and its 1st Battalion the road east and the high ground northeast of the town. In the meantime, seven miles northeast of Anyang-ni, in the vicinity of Hill 290, enemy forces ambushed the lead platoon of Company B, 1st Battalion, and seriously disorganized it. Closely pursued by the enemy, the company withdrew two miles southward toward the 1st Battalion's lines and halted the NKPA force. On the twenty-third the 1st Battalion resumed the offensive, seizing Hill 290. Situated three miles below the Han River and seven miles southeast of Yongdungp'o, Hill 290 dominated the southern approaches to the Han and to Seoul.
While the X Corps' southern flank was being secured by the 7th Division, the heaviest fighting in the battle for Seoul began on the city's western edge on 22 September and lasted four days. The NKPA's defensive line on the west side of Seoul was fixed firmly at the north on Hill 296, just south of the Kaesong highway and west of Seoul's Sodaemun Prison. The NKPA line curved from the crest of Hill 296 in a gentle half-moon sweep eastward and southward down spur ridges two and a half miles to the Han River, the concave side facing west toward the UN troops. Three hills, known as Hills 105 North, Center, and South, formed the greater part of this uneven ridgeline. Hills 105 Center and 105 South, through which the main Pusan-Manchuria rail line and road coursed into Seoul, completely dominated the area and contained a variety of field fortifications capable of quick organization for defense. Two miles east of these positions, in the center of the city, were the Government House and main railroad station.
The principal NKPA unit manning this line was the 25th Brigade. Formed a month earlier at Ch'orwon, it had begun moving to Seoul on the day of the Inch'on landing, with most of the unit arriving in the city on 19 September. The brigade numbered about twenty-five hundred men and probably consisted of two infantry battalions, four heavy machine gun battalions, an engineer battalion, a 76-mm. artillery battalion, a 120-mm. mortar battalion, and miscellaneous service troops. Along with the 78th Independent Regiment, it defended both the military and topographic crests. The slopes contained defensive positions -- deep foxholes, which offered protection from overhead shell air bursts; and concrete caves, which stored abundant supplies. More than fifty heavy machine guns, with interlocking fields of fire, dotted these slopes.
Starting on 22 September, the 5th Marines fought a series of hard battles as it attempted to clear the North Koreans from positions west of Seoul. The 5th was soon joined by two other regiments, as planned, but the enemy's stubborn defense had begun to worry the American commanders. On the twenty-third General Almond expressed to the 1st Marine Division commander, Maj. Gen. Oliver P. Smith, his dissatisfaction with the slow pace of the marines' progress, giving him twenty-four hours to gain ground. Otherwise, Almond told Smith that he would change the division boundaries and bring the 7th Division's 32d Infantry into the battle to envelop the enemy's defenses from the south.
On the morning of 24 September the North Koreans were still holding the marines in check west of Seoul. After conferring with the 7th Division commander, Maj. Gen. David G. Barr, Almond changed the boundary between Barr's and Smith's units. Early the next morning Barr's forces would attack across the Han River into the southeast portion of Seoul.
To support the 7th Division's crossing, the X Corps reinforced Barr with the Marines' 1st Amphibious Tractor Battalion (minus one company), two platoons of Company A, 56th Amphibious Tank and Tractor Battalion, and the ROK 17th Regiment. The division's 32d Infantry would spearhead the attack, with the crossing taking place at the Sinsa-ri ferry three miles east of the main rail and highway bridges over the Han River. The main rail line and highway on the east side of the city passed about a mile beyond the northern base of South Mountain (Nam-san), its nine hundred feet making it the highest point in Seoul.
For the crossing the 32d Infantry had a strength of over forty-nine hundred soldiers, of which slightly more than eighteen hundred were South Koreans. Its mission was threefold: take and secure South Mountain; secure Hill 120, situated two miles southeast of Seoul; and seize and hold Hill 348, a large high mass five miles east of the city.
The battle opened at 0600 on 25 September, when the 48th Field Artillery Battalion began firing a thirty-minute artillery preparation. Soon the heavy mortars joined in to hammer the cliffs that lined the opposite side of the river. At 0630, under the cover of ground fog, the 2d Battalion, 32d Infantry, crossed the Han. Upon reaching the other side, the soldiers scurried across the narrow riverbank and scaled the thirty- to sixty-foot cliffs. The river crossing apparently surprised the North Koreans, whose defenses were lightly manned. The Americans met only moderate resistance as they reached and cleared the summit of South Mountain by 1500.
Meanwhile, the 32d Infantry's 1st Battalion crossed the Han at 0830 and moved east along the riverbank toward Hill 120. Its 3d Battalion made its way to the other side of the river a little after noon, passed through the 1st Battalion's ranks, and took up positions on Hill 120 itself. The ROK 17th Regiment followed immediately behind the 3d Battalion and moved farther east to the 32d Infantry's extreme right flank, where, at 2150, it commenced an all-night attack against Hill 348.
Occupying a tight perimeter on top of South Mountain, the 2d Battalion's soldiers waited quietly but tensely throughout the night for the enemy's counterattack. The early morning hours passed slowly, without nearly a sound. Finally, at 0500 on 26 September, an NKPA force of approximately one thousand men charged Company G on the mountain's higher western knob and Company F on the lower eastern knob. Company G held its position, but F was overrun. After two more hours of fighting, the Americans restored their positions and forced the surviving North Koreans to retreat down the slopes.

Captured enemy weapons
(National Archives)
The same morning the 1st Battalion, to the east, also found itself heavily engaged while the 3d Battalion moved from Hill 120 to Hill 348. En route, the latter's Company L, commanded by 1st Lt. Harry J. McCaffrey, Jr., observed a large enemy column on the highway leaving Seoul. Seizing the opportunity, McCaffrey ordered his men to attack. Using surprise, the infantrymen destroyed or captured five tanks, more than forty other vehicles, three artillery pieces, and seven machine guns, as well as seized two ammunition dumps, clothing, and other supplies. About 500 NKPA soldiers, possibly members of a corps headquarters, were killed during the battle. American analysts believed that those killed constituted the principal enemy command defending Seoul.
During the 32d Infantry's assault on South Mountain, the marines ground down the hill defenses on Seoul's west side and entered Seoul proper on 25 September. By that time, the NKPA's 18th Division commander had decided that the battle was lost and began withdrawing his unit, which had been fighting in the Yongdungp'o area south of the Han River. To cover the division's northbound retreat, the North Koreans struck with desperate counterattacks at every point of the X Corps' advance into the city. Day-long street fighting ensued on the twenty-sixth. With snipers firing from houses and defenders manning barricades, each city block became a small battlefield. By nightfall X Corps soldiers controlled approximately half of Seoul.

Tanks of the 5th Marine Regimentpassing through a demolished barricade on the outskirts of Seoul to support the Marine assault
(National Archives)
Earlier that day General MacArthur had announced in a dispatch that Seoul had been completely enveloped and held by the ROK 17th Regiment and elements of the 7th Infantry and 1st Marine Divisions. Day-long street fighting, however, continued throughout the twenty-seventh. The defenders in the center of Seoul built chest-high barricades across the streets, from which they fired antitank guns and machine guns. Rocket attacks and strafing runs by U.S. Navy and Marine aircraft, mortar attacks, and fire from tanks were used to reduce the barricades. In some cases, a single barricade held up a battalion's advance by as much as an hour. During the night the last defenders, except for snipers and stragglers, finally withdrew from the city and all enemy resistance ended the next day. In a brief ceremony on 29 September General MacArthur returned control of Seoul to President Rhee.
The victory achieved in the fight for Inch'on and Seoul was not without cost. The X Corps' casualties totaled some 3,500. The 7th Division had 106 killed, 409 wounded, and 57 missing in action (these totals included 166 KATUSAs), and its 32d Infantry alone lost 66 killed, 272 wounded, and 47 missing. The 1st Marine Division suffered the heaviest losses -- 364 killed, 53 of whom died of wounds; 1,961 wounded; and 5 missing in action. Enemy casualties were estimated at 14,000 killed, and prisoners of war were confirmed at 7,000.
(BK Comment: Note that the Army ratio of MIA to total casualties was 50 times that of the Marine Corps. The ratio was even higher during the Perimeter fighting. In general, as compared to Army units, the Marines did not run, surrender, or abandon their wounded or dead. That was part of the Esprit of the USMC and one reason why they were generally successful in their vicious battles with the North Koreans and Chinese.)

Breakout and Pursuit
In the south the Eighth Army's battle line, at its closest point, was one hundred eighty miles by air from the X Corps' landing area in the enemy's rear. The winding mountain roads that lay ahead of the army made that distance even farther. After a slow start, however, the mileage was quickly covered as the American forces linked up south of Seoul.
As the X Corps secured Inch'on on 16 September, General Walker's Eighth Army pushed out of the Pusan Perimeter. The Eighth Army began its breakout on schedule at 0900. The offensive, however, was not simultaneous; many Eighth Army units were still repelling enemy attacks. The momentum of the breakout built slowly in the face of strong enemy resistance, centered on several hills that controlled the Eighth Army's main avenues of advance northward.
South of Waegwan, Hill 268 represented a critical terrain feature, for the main highway ran along the east bank of the Naktong River. The NKPA's tank-supported 3d Division defended this southern approach to the Waegwan-Taegu road. The hill was important tactically because of a gap in the enemy line to the south. The British 27th Brigade held vital blocking positions at the lower side of this gap, just above strong forces of the NKPA's 10th Division.
Moving along the east bank of the Naktong on 19 September, the 5th Regimental Combat Team, which was attached to the 1st Cavalry Division, began a full regimental assault against Hill 268. After a hard day of fighting the 5th took the hill, except for its northeast slope. By nightfall the 5th Infantry's 3d Battalion was on the hill; its 1st Battalion was pushing northwest toward another enemy position; and its 2d Battalion had captured Hill 121, one and a half miles north of Hill 268 and one mile short of Waegwan.
The battle for Hill 268 continued the next morning as more than two hundred NKPA soldiers in log-covered bunkers fought the 3d Battalion. Three flights of U.S. Air Force F-51 Mustang fighters dropped napalm, fired rockets, and strafed the enemy bunkers. Following the air strikes, the 5th Regimental Combat Team again struck at the bunkers, where, in many cases, the North Koreans fought to the last man. By noon the 5th controlled both the summit and slopes of the position.
With the loss of these key positions, the 3d Division's defenses around Waegwan broke apart and its troops began a panic-stricken retreat across the Naktong. Aerial observers estimated that fifteen hundred North Koreans crossed to the west side of the Naktong just above Waegwan. Further reports indicated that the roads north of the town were jammed with enemy soldiers in groups of ten to three hundred.

Waegwan. Further reports indicated that the roads north of the town were jammed with enemy soldiers in groups of ten to three hundred.
On 19 September the 5th Infantry's 2d Battalion traversed the Naktong River, took Waegwan, moved through the town to the southwest slope of Hill 303, and secured the hill on the twentieth. By the afternoon of the following day the entire 5th Regimental Combat Team was on the other side of the Naktong, and in a span of five days the 5th had crushed the 3d Division's right flank and part of its center. The enemy's advance positions on the road to Taegu, where the 1st Cavalry Division's 5th Cavalry found battle, were thus rendered indefensible.
Meanwhile, along its defensive line on the western edges of the Pusan Perimeter, the 25th Division was still fighting the NKPA's 6th and 7th Divisions on 16 September. The enemy appeared stronger than ever on the heights of Battle Mountain, P'il-bong, and Sobuk-san. The 24th Infantry, positioned in the center, faced the brunt of the enemy's daily attacks. The 27th Infantry was on its left and the 35th Infantry on its right, astride the east-west Masan-Chinju road. To counter the NKPA's offensive, the 25th Division's commander, Maj. Gen. William B. Kean, assembled a composite battalion-size task force to attack the enemy-held heights of Battle Mountain and P'il-bong. Heavily supported by fire from the 8th and 90th Field Artillery Battalions and by numerous air strikes, the task force attacked these heights repeatedly on the seventeenth and eighteenth. However, automatic weapons fire from well-prepared enemy positions drove back the Americans, who sustained heavy casualties. Company A, 27th Infantry, alone suffered 57 casualties in a period of twenty-four hours.
On the eighteenth, after failing to drive the enemy from the peaks, Kean dissolved the task force. The next morning he found that the North Koreans had abandoned their positions on the crest of Battle Mountain during the night, and the 1st Battalion, 24th Infantry, moved up and secured the area.
On 19 September the 35th Infantry on the right, or northern, flank met light resistance until it reached the high ground in front of Chungam-ni. There, in cleverly hidden spider holes, enemy troops fired on 1st Battalion soldiers from the rear. The next day the 1st Battalion captured Chungam-ni, and the 2d Battalion took the long ridgeline running northwest from Chungam-ni to the Nam River. To the south, heavy fighting on the 25th Division's left flank kept the 27th Infantry busy as it tried to move forward. On the twenty-first, three miles southwest of Chungam-ni, the 35th Infantry captured the well-known Notch and then moved rapidly west eight air miles without resistance to the high ground at the Chinju pass, only to be blocked by 6th Division elements protecting the unit's withdrawal across the Nam River and through Chinju some six miles to the west. At the same time, the 24th Infantry in the center and the 27th Infantry on the left advanced, slowed only by the rugged terrain. By the end of September the 25th Division had seized the west coast port of Kunsan.

A river crossing via an underwater bridge (left) and a makeshift ferry
(National Archives)
On the right flank of the Pusan Perimeter, in the mountainous region of the ROK II Corps, ROK 6th Division soldiers advanced slowly against the NKPA's 8th Division. After four days of battle the8th Division was destroyed as a combat force, suffering about four thousand casualties. Enemy survivors fled in disarray north toward Yech'on. By 21 September the ROK 6th Division, meeting little opposition, was advancing northward toward Uihung.
Farther to the east the ROK 8th Division found little opposition from the NKPA's 15th Division, which had been practically annihilated. On 16 September, in the ROK I Corps sector, elements of the ROK Capital Division fought their way through the streets of An'gang-ni. The next day, advancing from the west in the ROK II Corps sector, a battalion of the ROK 7th Division linked up with elements of the ROK Capital Division, closing a two-week-old gap between the ROK I and II Corps.

Infantrymen helping a wounded comrade (National Archives)
The NKPA's 12th Division waged a series of stubborn delaying actions against the ROK Capital Division in the vicinity of Kigye as the North Koreans retreated northward into the mountains. Kigye fell on 22 September. In the harbor village of P'ohang-dong fierce battles were fought between the ROK 3d Division and the NKPA's 5th Division. The ROK units finally captured the village during the morning of the twentieth. They continued to attack aggressively, forcing a disorderly withdrawal by the enemy toward Yongdok.
As MacArthur had anticipated, the North Korean Army was cut off and in retreat. By 23 September the enemy cordon around the Pusan Perimeter had been destroyed. The North Korean soldiers in the south had disintegrated as an effective military force; while some escaped to the north and others became guerrillas in the south, most were casualties. The breakout from the Pusan Perimeter cost the Eighth Army 790 killed and 3,544 wounded. But X Corps and Eighth Army soldiers had captured 23,000 enemy personnel and killed thousands more.
Crossing the 38th Parallel
As soon as UN leaders digested the allied success, they began to debate the advisability of crossing the 38th Parallel into North Korea. The National Security Council advised President Harry S. Truman against moving north. The council's position was that the expulsion of the North Koreans from South Korea was a sufficient victory. The Joint Chiefs of Staff disagreed, however, claiming military doctrine demanded that the North Korean Army be destroyed completely to prevent renewed aggression. President Truman, on 11 September, adopted the arguments of his military advisers while heeding the National Security Council's call to avoid provoking Communist China and the Soviet Union.
Thus, on 27 September, the Joint Chiefs directed General MacArthur to cross the 38th Parallel for the purpose of destroying North Korea's military forces, providing that no Chinese or Soviet forces had entered, or threatened to enter, North Korea. They further decreed that UN troops were not to go into China or the Soviet Union and that only ROK soldiers should operate along these borders. Secretary of Defense George C. Marshall, on the twenty-ninth, sent MacArthur a personal message that confirmed his approval for tactical and strategic operations north of the parallel. This message, MacArthur was told, had been personally endorsed by Truman. MacArthur received a secondary mission to unite all of Korea, if possible, under President Rhee.
The responses to this decision were immediate and strong. On 1 October Premier Chou En-lai warned that China would not tolerate or stand aside if UN forces invaded North Korea. This was a clear threat that China would intervene if that should happen. On the second the Soviet delegate to the United Nations proposed that a cease-fire in Korea be called and that all foreign troops be withdrawn. The following day the Indian delegate expressed his government's position that UN forces should not cross the 38th Parallel.
General MacArthur, on 1 October, sent a message to the commander in chief of the North Korean forces, demanding that the North Koreans lay down their arms and cease hostilities under UN military supervision so as to avoid further loss of life and destruction of property. The message also called for the release of UN prisoners of war and civilian internees. But North Korea ignored the proposals. MacArthur issued a last chance ultimatum for North Korea to surrender on the ninth. While North Korea did not respond officially, Premier Kim Il Sung rejected it the following day in a radio broadcast. Meanwhile, on the seventh, the UN General Assembly had passed a resolution calling for the unification of Korea and authorizing MacArthur to send troops across the 38th Parallel.
With the IX Corps positioned to protect the lines of communications south of the Han River, which flows east to west south of Seoul, General Walker ordered the I Corps, with the 1st Cavalry, 24th Infantry, and ROK 1st Divisions, to assemble in the vicinity of Kaesong, northwest of Seoul just below the 38th Parallel. Upon receipt of orders, the ROK II Corps, composed of the 6th, 7th, and 8th Divisions, moved to the area between Ch'unch'on and Uijongbu in central Korea and the ROK I Corps, which consisted of the Capital and 3d Divisions, to the area between Yongp'o and Chumunjin-up on Korea's east coast. While these forces prepared to attack northward, X Corps elements boarded ships at Inch'on and Pusan for an amphibious landing at Wonsan, a major port on North Korea's east coast one hundred ten miles above the 38th Parallel.
On 29 September a message, dropped from a light plane by an officer with the Military Advisory Group to the Republic of Korea, was delivered to the U.S. adviser to the ROK 3d Division, Lt. Col. Rollins S. Emmerich. According to the message, the ROK 3d Division was to cross the 38th Parallel and proceed to Wonsan as soon as possible. The next day the division crossed the parallel and advanced up the east coast. The ROK Capital Division followed. After establishing command posts at Yangyang, eight miles north of the parallel, on 2 October, both divisions proceeded to Wonsan and captured the town on the tenth, well before the X Corps had landed.
At Kaesong the 1st Cavalry Division was ready to cross the line. The 8th Cavalry, in the center, was to attack frontally from Kaesong to Kumch'on, fifteen miles north and along the main highway axis; and the 5th Cavalry, on the right, was to move east and then swing west in a circular flanking movement, designed to trap enemy forces south of Kumch'on. In the meantime, the 7th Cavalry, on the division's left, traversed the Yesong River; advanced north on the road from Paekch'on to the small town of Hanp'o-ri, six miles north of Kumch'on, where the main P'yongyang road crossed the Yesong River; and established a blocking position. Defending the Kumch'on area north of Kaesong were the NKPA's 19th and 27th Divisions. Its 43d Division, to the west, defended the Yesong River crossing and the coastal area beyond the river.
At 0900 on 9 October the 1st Cavalry Division struck out across the 38th Parallel. Initially, the advance was slow. Along the main highway the 8th Cavalry stopped repeatedly and waited for engineer troops to clear mines from the road. Halfway to Kumch'on on the twelfth the regiment was halted by an enemy strongpoint, defended by tanks, self-propelled guns, and antiaircraft weapons. In spite of a sixteen-plane air strike and a 155-mm. howitzer barrage, the strongpoint held.

1st Cavalry Division troops pursuing the enemy north of Kaesong
(National Archives)
The 5th Cavalry, which also ran into trouble at the start, failed to cross the parallel until 10 October. The next day its 1st Battalion encountered an enemy force holding a long ridge with several knobs -- Hills 179, 175, and 174 -- that dominated a pass fifteen miles northeast of Kaesong. The infantrymen drove the defenders from the ridge during the afternoon of the twelfth, but the fight was fierce. In the battle for Hill 174 1st Lt. Samuel S. Coursen, a platoon leader in Company C, observing that one of his men had entered a well-hidden gun emplacement, thought to be unoccupied, and had taken a bullet, ran to his aid. Without regard for his personal safety, Lieutenant Coursen engaged the enemy in hand-to-hand combat in an effort to protect the wounded soldier until he himself was killed. When his body was recovered after the battle, 7 enemy dead were found in the emplacement. Coursen's actions saved the wounded soldier's life and eliminated the main position of the enemy roadblock. For his actions, Lieutenant Coursen received the Medal of Honor posthumously.
After much fighting, the 1st Cavalry Division captured Kumch'on on 14 October. With I Corps soldiers moving through the enemy's principal fortified positions between the 38th Parallel and P'yongyang, the North Korean capital city, enemy front lines as such ceased to exist. On the nineteenth Company F, 5th Cavalry, entered P'yongyang, followed shortly thereafter by ROK 1st Division elements from the northeast. The next morning, the fifteenth, the ROK 1st Division reached the heart of the city and took the strongly fortified administrative center without difficulty. The entire city was secured by 1000 that day.

Soldiers of the 5th Cavalry advancing on P'yongyang
(National Archives)
On Korea's east coast, the X Corps' 1st Marine Division went ashore at Wonsan on 26 October and its 7th Division landed unopposed at Iwon, eighty miles north of Wonsan, on the twenty-ninth. Once in place, X Corps forces began to secure key industrial and communications areas, port installations, and the power and irrigation plants in northeastern Korea.
On 24 October General Walker took personal command of his advance Eighth Army headquarters in P'yongyang, located in the same building that had been the headquarters of Premier Kim Il Sung. In retrospect, the Eighth Army had accomplished much in a short period of time. Less than six weeks had passed since the army had fought desperately to hold its lines three hundred twenty miles to the south along the Pusan Perimeter. Likewise, the Inch'on landing was less than six weeks in the past and it was four weeks since the recapture of Seoul. Having broken out of its embattled perimeter and pushing northward, the Eighth Army was now one hundred sixty miles north of Seoul and one hundred thirty miles inside North Korean territory. After many hard-fought battles between the perimeter and P'yongyang, it had succeeded in overrunning the enemy's capital city and was about to breach the last important river barrier south of North Korea's northern border.
The Yalu River
With the North Korean capital city secured, the Eighth Army continued its push northward toward the Yalu River, Korea's traditional border with China. The Ch'ongch'on River and its tributaries, the Kuryong and Taeryong Rivers, all flowing from the north, formed the last major water barrier in the western part of North Korea short of the border. At this point in time, the Ch'ongch'on River was the principal terrain feature in the Eighth Army's field of operations, and it largely dictated the army's deployment and tactical maneuvers.
The Eighth Army's operations above the Ch'ongch'on River were essentially a continuation of the pursuit that started with the breakout from the Pusan Perimeter. Moving northward, the I Corps, with the 24th Division and the attached British 27th Brigade positioned on the left, proceeded to the Ch'ongch'on; the ROK II Corps, with the ROK 1st Division, advanced on the right. To the east the ROK 8th Division reached Tokch'on, forty miles north of P'yongyang, during the night of 23 October and then turned north and arrived at Kujang-dong on the Ch'ongch'on, about ten miles from Tokch'on, two days later. The ROK 6th Division, meeting little opposition and traveling fast up the Ch'ongch'on River valley, reached Huich'on, nearly sixteen miles north of Kujang-dong, on the night of the twenty-third. Passing through Onjong, twenty-six miles from Huich'on, during the night of the twenty-fourth, the 7th Regiment, ROK 6th Division, turned north and advanced toward Ch'osan, fifty miles away on the Yalu River. A reinforced reconnaissance platoon from the 7th Regiment entered Ch'osan the next morning and found the North Koreans retreating across the Yalu into China over a narrow floating footbridge.
In the meantime, on 22 October the 24th Division, having been relieved by the 2d Division, moved northward from P'yongyang, its mission to push the North Koreans against the 187th Airborne Infantry's blocking position, thus cutting off the enemy's escape route and, it was hoped, rescuing prisoners of war. Elements of the 24th Division continued to press northward, and the 1st Battalion, 21st Infantry, reached Chonggo-dong, just southwest of Sinuiju on the Yalu River, the northernmost penetration of the Eighth Army.
China Intervenes
Late in October, in the mountainous region above P'yongyang, the Eighth Army was poised to cross the Ch'ongch'on River in full force. On North Korea's east coast, across the formidable barrier of the Taebaek Mountains, X Corps forces were landing and beginning
their drive to the Yalu. Morale among the American and allied soldiers was high, for many thought that this river crossing would be the last brief phase of the war. But then the unexpected happened: China entered the war.
On 25 October, in the ROK II Corps sector, the 3d Battalion, 2d Regiment, ROK 6th Division, started northwest from Onjong, about fifty miles from the Yalu, toward Pukchin. Eight miles west of Onjong the 3d Battalion encountered what was thought to be a small force of North Koreans but was, in reality, a Communist Chinese forces (CCF) trap, in which CCF troops destroyed the 3d Battalion as an organized force. On the evening of the next day the division ordered its 7th Regiment to withdraw south. Before it could do so, however, it needed supplies, which were airdropped on the twenty-eighth. As the 7th Regiment headed south the following morning, it ran into an enemy roadblock about twenty miles south of Kojang.
More attacks followed on 31 October as CCF troops broke through the sector of the 16th Regiment, ROK 8th Division, near its boundary with the ROK 1st Division. By the next day the Chinese had pushed the ROK 7th Division back to the vicinity of Won-ni. The series of attacks forced the ROK II Corps to pivot facing east, causing a gap between its left flank and the U.S. I Corps. Walker quickly assembled the 2d Division in the Sunch'on area to meet any possible emergency in this gap. Within a few days of the first battles the CCF troops had driven back and severely crippled the ROK II Corps and had moved south of the Ch'ongch'on River to the U.S. I Corps' open right flank.
In the far west, the story was the same. As part of the U.S. I Corps' general advance on 25 October, the ROK 1st Division was spread out on the road that ran from the Ch'ongch'on River to Unsan. The division's 15th Regiment passed through Yongbyon and continued toward Unsan without opposition. In the lead were elements of Company D, 6th Medium Tank Battalion, which also passed through Unsan without incident. Just before 1100, as the tanks approached a bridge one and a half miles northeast of the town, enemy mortar fire blew the bridge. Engaging the enemy force, the South Korean soldiers reported a half-hour later that three hundred Chinese troops were in the hills just north of Unsan. Second in the division column, the ROK 12th Regiment turned west when it arrived at Unsan. It, too, ran into the Chinese just beyond the town. The CCF's attacks against the ROK 1st Division continued on the twenty-sixth but eased up the following day.
As reports from the front reached the Eighth Army headquarters that prisoners captured by ROK soldiers were Chinese, General Walker became concerned. On 28 October he relieved the 1st Cavalry Division of its security mission in P'yongyang. The division's new orders were to pass through the ROK 1st Division's lines at Unsan and attack toward the Yalu River. Leading the way on the twenty-ninth, the 8th Cavalry departed P'yongyang and reached Yongsan-dong that evening. The 5th Cavalry arrived the next morning, with the mission to protect the 8th Cavalry's rear. With the arrival of the 8th Cavalry at Unsan on the thirty-first, the ROK 1st Division redeployed to positions northeast, east, and southeast of Unsan; the 8th Cavalry took up positions north, west, and south of the town. Meanwhile, the ROK 15th Regiment was desperately trying to hold its position east of the 8th Cavalry, across the Samt'an River.
During the afternoon of 1 November the CCF's attack north of Unsan gained strength against the ROK 15th Regiment and gradually extended to the right flank of the 1st Battalion, 8th Cavalry. At nightfall the 1st Battalion controlled the northern approaches to the Samt'an River, except for portions of the ROK 15th Regiment's zone on the east side. The battalion's position on the left was weak; there were not enough soldiers to extend the defensive line to the main ridge leading into Unsan. This left a gap between the 1st and 2d Battalions. East of the Samt'an the ROK 15th Regiment was under heavy attack, and shortly after midnight it no longer existed as a combat force.
The ordeal of the 8th Cavalry now began. At 1930 on 1 November the Chinese attacked the 1st Battalion, 8th Cavalry, all along its line. At 2100 CCF troops found the weak link in the ridgeline and began moving through it and down the ridge behind the 2d Battalion, penetrating its right flank and encircling its left. Now both the 1st and 2d Battalions were engaged by the enemy on several sides. Around midnight the 8th Cavalry received orders to withdraw southward to Ipsok.
As of 0130 on 2 November there were no reports of enemy activity in the 3d Battalion's sector south of Unsan. But as the 8th Cavalry withdrew, all three battalions became trapped by CCF roadblocks south of Unsan during the early morning hours. Members of the 1st Battalion who were able to escape reached the Ipsok area. A head count showed that the battalion had lost about 15 officers and 250 enlisted men. Members of the 2d Battalion, for the most part, scattered into the hills. Many of them reached the ROK lines near Ipsok. Others met up with the 3d Battalion, the hardest hit. Around 0300 the Chinese launched a surprise attack on the battalion command post. Hand-to-hand fighting ensued for about half an hour before the enemy was driven from the area. The disorganized members of the 3d Battalion formed a core of resistance around three tanks on the valley floor and held off the enemy until daylight. By that time only 6 officers and 200 enlisted men were still able to function. More than 170 were wounded, and there was no account of the number dead or missing. Attempts by the 5th Cavalry to relieve the beleaguered battalion were unsuccessful, and the 3d Battalion, 8th Cavalry, soon ceased to exist as an organized force.
The enemy force that brought tragedy to the 8th Cavalry at Unsan was the CCF's 116th Division. Elements of the 116th's 347th Regiment were responsible for the roadblock south of Unsan. Also engaged in the Unsan action was the CCF's 115th Division. The arrival of the Chinese was obviously now going to have a dramatic impact on the course of the war.
Analysis
For the United Nations forces, victory was in the air by early October 1950. The Inch'on landing and the breakout from the Pusan Perimeter had destroyed the North Korean units operating south of the 38th Parallel. With the return of Seoul to the South Korean government, the Republic of Korea regained the status it had enjoyed before the 25 June invasion. To stop at this juncture would have been consistent with America's policy of containment. However, substantial reasons existed for carrying the war into North Korea. An estimated thirty thousand NKPA soldiers had escaped over the border, with an additional thirty thousand in northern training camps. Combined, these numbers represented enough troops to fill six divisions, and South Korea's military forces were, if anything, even weaker than they had been before the invasion. At best, a halt would have compelled the United Nations Command to maintain a presence along the 38th Parallel indefinitely or risk another invasion of South Korea.
By all appearances, a complete military victory was within easy grasp. However, the decision to cross the 38th Parallel appears, in retrospect, to have been the turning point in the Korean War. Communist China had warned that it might intervene if foreign forces crossed the parallel. The warning had gone unheeded. In response, nearly one hundred eighty thousand CCF soldiers secretly crossed the Yalu River between 14 October and 1 November. General MacArthur, unaware of the full extent of Communist China's commitment, believed that the attack on 25 October was a token gesture rather than a serious intercession. But, by early November, intelligence officers had amassed undeniable evidence that the Chinese had indeed intervened in strength. Eighth Army troops found themselves once more on the defensive, being pushed southward. The course of the war had changed again.
(BK Comment: I would much prefer not to make any comments in these Army historical sites, but they consistently leave out information which might help understand Eighth Army's generally poor performance during the first six months of the war, particularly their disaster when counterattacked by the Chinese. When the CCF began their 1st Phase Offensive, they did indeed crush the Army and ROK units they attacked, but they also did indeed suffer a devastating defeat in the East, where their 124th Division was virtually destroyed by the 7th Marine Regiment. It has always frustrated me that the Army failed to recognize the consistently superior performance by USMC infantry against the same enemy that consistently routed Army units. There is obviously much to be learned about training, tactics, and leadership requirements for troops engaging a determined and resourceful enemy on the ground. With its apparent inter-service bias the Army seems to be failing to do that. If true, this failure will cost many, many lives in the future, such as in our present war against terrorism, should we once again deploy infantry against a resolute foe.)

Further Readings

Appleman, Roy E. South to the Naktong, North to the Yalu (June-November 1950). United States Army in the Korean War. Washington, D.C.: U.S. Army Center of Military History, 1961.

Sandler, Stanley, ed. The Korean War: An Encyclopedia. Military History of the United States, vol. 4. New York: Garland Publishing, 1995.

Summers, Harry G., Jr. Korean War Almanac. New York: Facts on File, 1990.

United States Military Academy, Department of Military Art and Engineering. Operations in Korea. West Point, N.Y.: United States Military Academy, 1956.

— — — . The West Point Atlas of American Wars. Edited by Vincent J. Esposito. Vol. 2. 1900-1953. New York: Frederick A. Praeger, 1959.

Cover: Men of the 32d Infantry, 7th Infantry Division, Marching through a village near Inch'on (National Archives)