Korea (Chosan in Korean, Chosen to the Japanese) had been an empire since 2333 BC. Its strategic location meant that it was coveted by both China and Japan, empires with which Korea experienced varied and complex relations, never as allies, but as a country desired as something to possess. Japan occupied Korea during the 1904–05 Japan–Russian War and annexed it in 1910. They undertook extensive efforts to incorporate Korea into the empire in order to exploit its resources and people. Koreans were third-class citizens within their own land, and the Japanese ran all aspects of the colony, from the government to installing Japanese managers to operate businesses. Japanese was taught in schools, and all facets of Korean culture and traditions were suppressed. It even became mandatory for Koreans to adopt Japanese names. During World War II the Japanese exploited Korean industry and agriculture to support their war effort. Millions of Koreans were drafted into the armed forces, employed in industry, or even shipped to Japan, and forced into service as laborers and comfort women throughout the occupied countries.
With the end of the war, XXIV US Corps occupied southern Korea on September 4, 1945 while the Soviet Red Army occupied the north from August 12, the dividing line being the 38th Parallel just north of Seoul. While the United Nations sought national elections to re-unify the country, it was not to be. Backed by the USSR and Communist China, the Democratic People’s Republic of Korea – North Korea (NK) – was established on August 15, 1948 with no intention of uniting with the south unless it was in control. Soviet occupation forces departed in December 1948 leaving their equipment behind. The division was unequal in both area and population. The south consisted of 37,000 square miles and a population of 21 million, while the north had 9 million people in 48,000 square miles.
South Korean refugees wait their turn to cross the Han River as the North Koreans approach. The military would not let them cross on the bridges for fear of saboteurs, so log and plank rafts were built alongside the supports. The bridges were destroyed on June 28. (USMC)
A marine automatic rifleman hammers rounds at an NK position from behind an overrun street barricade. The BAR was an accurate weapon; with its 20-round magazine and using the slow rate of fire it was easy to put bullets through a window or small opening. (USA)
The Korean People’s Army (KPA) was formally established on August 15, 1948, but its formation had begun in 1946 under cover of the Peace Preservation Corps. Combat units were covertly organized under the guise of security force training schools, which provided leaders and cadres for the first divisions. By the time of the North Korean invasion of the south, three corps, ten infantry divisions, an armored brigade, and numerous support and security units had been raised, along with a small air force and navy, as well as a border constabulary. The USSR provided thousands of advisers, and most of the weapons, equipment, munitions, and supplies to the KPA, in addition to training thousands of technicians and specialists inside the USSR. At the time of the invasion the KPA contained 223,080 troops.
The Republic of Korea (ROK – pronounced “rock”), was proclaimed on August 15, 1948 after UN-supervised elections.1 The ROK Army (ROKA) was established on the same date from the existing Korean Constabulary, which itself dated from 1946. The last US occupation troops departed in June 1949. At the time of the invasion the fledgling ROKA possessed eight under-strength and partly trained and equipped divisions with a total of 98,000 men. Besides securing the 38th Parallel, part of the army was engaged in combating northern guerrillas.
The Communist invasion caught the US and ROK completely by surprise when NK troops poured across the 38th Parallel at 0400hrs on June 25, 1950. The main North Korean attack was aimed at Seoul, and the victorious divisions continued to press south. Events occurred rapidly. US forces were authorized to conduct combat operations; the UN passed a resolution approving the use of armed force to restore peace; Seoul fell three days after the invasion and Inch’on on July 3. A small US combat element, Task Force Smith, was deployed to Korea from Japan arriving on July 1 and was defeated two days later. Subsequent US efforts were defeated and the battered ROKA was pushed south. US units, inadequately trained and equipped from occupation duty in Japan, were rushed in, along with Commonwealth forces. Efforts to establish defensive lines failed and the UN forces were pushed into the southeast corner by August 4 to make what many perceived as a last stand at Pusan. UN reinforcements continued to arrive and for the next month and a half the NK forces battered themselves against a stout defense. By mid-September the NK divisions were spent and few reinforcements arrived. Their ammunition and supplies were running out, while the UN forces within the perimeter continued to receive reinforcements and supplies.
Even before the tide had turned against the North Koreans, Gen Douglas MacArthur was making plans to break out of the Pusan perimeter, conduct a dramatic outflanking amphibious assault to cut the enemy’s supply line, and drive them north beyond the 38th Parallel. For an army tottering on the brink of defeat just weeks before, the plan could be considered nothing but bold and audacious, and, many said, bound to fail.
In mid-1950 the US Army and Marine Corps were a shadow of themselves five years previously, as were the navy and the air force (which had only become service separate from the army in 1947). The US armed forces had just undergone a major transformation. Instead of separate departments of war and navy co-ordinated by the Joint Chiefs of Staff (JCS), they were now under the Department of Defense, of which the JCS was a component. Answering to the Department of Defense were the departments of the army, navy, and air force. A civilian secretary headed each department, who answered to the the president, the Commander-in-Chief.
While all the armed services suffered from rapid postwar reductions, the Army was in particularly bad shape. It had declined in size from 89 divisions on V-J Day, to seven infantry, two airborne, and one armored division in 1950. With the exception of the 1st InfDiv in Germany and the 82d Airborne Division (AbnDiv) in the States, all were severely under strength. Rather than the 18,804 men they should have mustered at full strength, they contained between 11,000 and 13,650 men. The Army itself was authorized 610,900 personnel, but only 593,000 were on the rolls. The divisions were essentially gutted. The three infantry regiments lacked their third battalions; each battalion had only two companies, and the companies themselves only two platoons. There were 36 rifle platoons in a division instead of the required 81. Divisional tank and AAA battalions had only a single company/battery and lacked a battalion headquarters. Field artillery and engineer battalions had only two companies/batteries. The batteries had four howitzers instead of six. Infantry regiment tank companies were non-existent. Other divisional units were likewise reduced and older equipment was mostly in use for training, which also suffered. Emphasis was placed on providing training in skills useful in the civilian world as well as civilian education. Combat training was seldom undertaken and then only at the small unit level. The four infantry divisions (1st Cavalry, 7th, 24th, 25th Infantry) on occupation duty in Japan were in even worse shape because of training restrictions. The poor state of Japanese roads and bridges meant that only light tanks were issued. Live range-firing was almost unheard of. The turnover rate was over 40 percent a year.
The Marine Corps was in equally dire straits – if not worse. The corps consisted of two under-strength divisions, down from six wartime units. Few support units existed and Marine Aviation consisted of 16 squadrons, four with jets. Of the 74,279 marines, fewer than one third were in the Fleet Marine Force, the corps’ combat units. The 1st Marine Division (MarDiv) in California had 8,000 men with only one three-battalion regiment and a single artillery battalion. The 2d MarDiv in North Carolina had two infantry regiments, but one had only two battalions, and three artillery battalions to total 9,000 troops. War-strength divisions were authorized at 22,000 troops. It was intended that combat units would be removed from the Marine Corps, and their ground and air assets would be redeployed to the other services, reducing the service to a naval base security force and provider of troops to ships’ detachments.
To aggravate this situation, even though the US was now expected to be deployable worldwide because of the emerging Cold War conflicts, only limited sea and airlift deployment capabilities existed. Overseas logistics infrastructure was also wanting. The US was ill-prepared to deploy and sustain combat forces in remote underdeveloped theaters. The US armed forces, though, had one thing going for them: many of the officers (even at company level) and the NCOs had combat experience. Command and control systems, logistics support, training techniques, and tactics were well developed, and the many lessons learned during World War II had been studied and incorporated into doctrine.
The 11th Marines’ 105mm M2A1 howitzer prepares for a fire mission. Three battalions in both marine and Army divisions were armed with this excellent weapon. (USMC)
The Eighth US Army occupying Japan was mainly concerned with defending the Home Islands in the event of invasion by the USSR – an unlikely scenario. No planning was conducted for contingency operations in the Far East in response to small-scale regional conflicts. No defensive plans were made for Korea.
When the NK hordes swarmed across the 38th Parallel, the four occupation divisions in Japan were far from prepared. TF Smith, an under-strength battalion, was rushed to Korea by the 24th InfDiv in the first days and was easily brushed aside. The two-battalion 34th Infantry Regiment which followed almost immediately suffered a similar defeat.
The remnants of five ROK divisions with 45,000 men defended the north side of the 160-mile Pusan perimeter, while the 1st Cav and 24th and 25th InfDivs defended the west side with 30,000 troops. The 2d US InfDiv, the 1st Prov MarBde, and 27th British Infantry Brigade arrived at the end of July and beginning of August. Tank battalions, third battalions for the infantry regiments, artillery batteries, replacements, and supplies were flooding into Pusan.
The marine brigade was rushed to Pusan in response to MacArthur’s plea for help. His World War II experience had shown him the value of the marines and he also wanted an amphibious force. MacArthur’s plans saw far beyond the immediate defensive battle. The 1st MarDiv, from which the marine brigade had been spawned, was still rebuilding its strength for deployment to Korea. MacArthur had long-range plans for this unit as well. The 7th InfDiv was still in Japan, having been gutted and was being refilled to serve as the Far East Command (FECOM) Reserve. This unit, too, would serve his future plans.
As beaten ROK and US forces plunged south before the North Korean onslaught, MacArthur’s mindset was far from defeatist. The contemporary media (and later historians) often describe the Pusan perimeter as a last stand, a defeat in the making, and predicted an “American Dunkirk.” In reality, the battered Eighth Army was now positioned to defeat the NK in detail. The Eighth Army had suffered 6,000 US and 70,000 ROK casualties. The ten NK divisions, however, had shrunk to a few thousand exhausted fighters each. The NK had lost almost 58,000 troops and only 40-plus T34 tanks were thought to remain out of 150. Only about 21,000 were veteran troops, the rest being raw recruits whose morale was plummeting. Their supply line, running almost 300 miles from Pyongyang, the NK capital, and through Seoul to the units scattered on a wide front, was over-extended and under UN air and naval attack. Ample air support was provided to the Pusan perimeter from carriers and bases in Japan, only a couple of hundred miles away. The surviving NK now faced 92,000 well supplied and well supported UN troops, some of them fresh.
Marines, covered by a M26 tank, fight their way through the city street by street. Seoul’s heavily constructed buildings served the NK as ready-made strongpoints. (USMC)
All that MacArthur felt needed to be done to accommodate a breakout, a counteroffensive to drive the invaders back north, was to sever the fragile NK supply line, but he needed the tools to do it, and it was questionable whether they would be made available. While units and commands worldwide were being combed for troops and equipment there were valid concerns that the whole matter might be a diversion for a Soviet invasion of West Germany. The 82d AbnDiv, though requested by MacArthur, was untouchable as was the 1st InfDiv in Germany. The 82d was all that remained of the General Reserve; other divisions being gutted. The two under-strength marine divisions were needed for other contingencies. MacArthur had requested a marine division, but the JCS said they were unavailable. For what he had in mind he also needed an army division, and none was readily available.
FECOM possessed no amphibious capability. The marine brigade on Guam had been disbanded in April 1949. No viable amphibious training had been undertaken by the divisions in Japan or by any other army division. In late 1949, as a contingency for a Soviet invasion of Japan, joint navy and marine training teams were formed to train one regiment in each of the four divisions for amphibious counter-landings. The program had only just begun at the time of the invasion. The first concept of a flanking amphibious operation on the Korean peninsula was a modest effort involving the 1st Cavalry Division (CavDiv) still in Japan. The amphibious training teams were retasked to provide as much training as possible to the 1st Cav in the short time available. Operation Bluehearts, though, degenerated into simply landing the 1st Cav as reinforcements for Pusan.
By any rational assessment the two undermanned, under-equipped, untrained divisions tasked with the Inch’on–Seoul operation were incapable of accomplishing the mission.
MacArthur had immediately asked the Joint Chiefs of Staff (JCS) for a marine division, but had been told none was available. It appears, however, that this decision was made by the JCS without consulting the Navy Department. On June 28 the Commandant of the Marine Corps recommended to the Chief of Naval Operations that a marine unit be committed to Korea, and Commander, Naval Forces, Far East was advised that a Marine Regimental Combat Team (RCT) was available. So, on July 2, the day TF Smith battalion arrived in Korea, MacArthur, requested a marine RCT2 accompanied by air support, knowing that the marines could quickly field one. Discussions were also underway to prepare a marine division as a reserve for Korea.
Marines carry a wounded comrade across bullet-swept streets in the suburbs of Seoul. Even after an area had been cleared there was still a constant danger from bypassed and infiltrating snipers. (USMC)
The 1st Provisional Marine Brigade (1st Prov MarBde) was hastily formed at Camp Pendleton, California on July 7 under BGen Edward A. Craig and built around the 5th Marines and Marine Aircraft Group 33 (MAG-33). More than just an RCT, the brigade consisted of a full complement of support units. The 1st MarDiv was gutted to form the brigade and troops were flown in from the 2d MarDiv. The three infantry battalions were each a rifle company short, but third rifle platoons were assembled for the six companies, although they were still each 50 men short. The tank company, trained on M4A3 Shermans, was outfitted with M26 Pershings pulled from storage. The infantrymen were armed with the new 3.5in. bazooka; it was already clear that the 2.36in. was worthless against T34s. MAG-33 was assigned three F4U Corsair fighter squadrons, one night-fighter-equipped, plus an observation squadron with spotter planes and helicopters. The brigade shipped out July 12–14 with over 6,500 personnel. Without benefit of collective training, the brigade was assembled from men of many units, completely re-equipped, embarked, and on its way in a week. While en route to Japan, the brigade’s ground element was ordered directly to Pusan because of the deteriorating situation. It arrived on August 2 and was immediately thrown into the perimeter. On the 6th, in conjunction with 25th InfDiv elements, the brigade launched an attack westward to throw the enemy off balance. On the 12th the brigade was ordered to move north to support the 24th InfDiv during the battle of the Naktong. Committed to action on the 17th, the brigade was instrumental in recovering lost ground. The brigade was placed in reserve on the 21st and it received replacements and training. As higher headquarters fought over the question of employing the brigade in the planned Inch’on landing, it was returned to the Naktong Bulge on September 1, which had again been overrun. It helped restore the situation and the overall action helped break the back of the final NK offensive to carry the Pusan perimeter. Assembling at Pusan on September 7, the exhausted marines found third companies had arrived for each battalion along with replacements. They also found they were departing Pusan for points unknown. A hurried week was spent re-organizing, incorporating and training replacements, re-equipping, training the attached 1st Korean Marine Corps (KMC) Regiment, and embarking aboard ships. The brigade sailed on the 15th having been formally disbanded and re-incorporated into the 1stMarDiv.
Marine aviation would play an important role in the Inch’on–Seoul Campaign, both carrier- and land-based. This Marine Fighter Squadron 312 “Checkboards” F4U-4B Corsair sits on Kimpo Airfield. (USMC)
While the 1st Prov MarBde was making history at Pusan, the Marine Corps was frantically preparing the 1st MarDiv to follow. Marine units throughout the corps were stripped of men to fill the division. It contained less than 3,400 troops when the brigade departed and the 1st Marine Aircraft Wing (1st MAW), which would accompany the division, about 2,500. Not only did these two units have to be rebuilt and deployed, but the 2d MarDiv, 2d MAW, and numerous non-divisional units had to be filled. The 129,000 Marine Reservists were immediately mobilized and Marine Security Forces and other branches contributed 50 percent of their personnel. In the first week of August, almost 14,000 regulars and reservists arrived at Camp Pendleton. The first divisional units were scheduled to depart on August 10 and for all practical purposes the units did not exist. The 1st Marines was built from scratch, as were other units. The 2d MarDiv’s three artillery battalions were sent from North Carolina; the 1st MarDiv’s only artillery battalion was with the brigade. The second regiment would be provided by the 1st Prov MarBde, which would be absorbed into the division. Once pulled from the Pusan perimeter it would be leading the Inch’on assault ten days later. The third regiment, ordered raised on August 10, and other supporting units would come partly from the 2d MarDiv. This regiment, the 7th Marines, would not depart for Korea until September 3. It was built from the 6th Marines which arrived at Pendleton on August 16 with two weak battalions along with other 2d MarDiv troops. The 6th’s 3d Battalion was afloat in the Mediterranean and would join the regiment in Korea via the Suez Canal. RCT-7 would follow later. What little training time was available was spent on conditioning drills and test-firing weapons.
The USS George Clymer (APA-27) prepares to cast off for Inch’on at Kobe. Landing craft, medium (LCM) can be seen on the aft cargo deck. (USN)
The 1st MarDiv sailed August 10–22, but it was really only a third of a division, with the 5th Marines already in Korea and the 7th Marines to follow. The supporting battalions had only one or two companies as the others were with RCT-5 and RCT-7. Staff groups were flown ahead to Korea to begin planning and to co-ordinate the division’s arrival. The division arrived at Kobe, Japan between August 29 and September 3. Little time remained until the scheduled September 15 Inch’on landing. Individual and amphibious instruction took place aboard ships. Little field training time was granted at Kobe because of the need to undertake additional combat-loading of equipment and supplies, and this was further hampered by a typhoon.
The 1st MarDiv comprised a core of regulars with combat experience, officers and NCOs. Virtually all company commanders and up had seen combat. However, most of the active-duty junior officers, junior NCOs, and enlisted men had no combat experience, while of the reservists, 99 percent of the officers and 77.5 percent of the enlisted were World War II veterans.
A combined arms brigade, where none had existed, had been raised, deployed, and successfully committed to combat in four weeks. A division with only 2,500 troops was filled out, shipped, and conducted an amphibious assault in eight weeks. The fact that these formations were thrown together from scores of units, manned by regulars and reservists who just weeks before were pursuing civilian endeavors, and had been afforded virtually no collective or large unit tactical training can be described as nothing less than a phenomenal feat.
In many ways the second division to participate in the Inch’on–Seoul operation was in worse shape than the 1st MarDiv. The 7th InfDiv was headquartered in Sapporo on Hokkaido, the second northernmost of the Japanese Home Islands. Like the other three occupation divisions, it was several thousand men under-strength when the war began. The division was severely gutted to fill the other three as they deployed to Korea. Three infantry battalions were broken up as fillers for the 1st CavDiv. Some 1,640 troops were re-assigned to the 24th and 25th InfDivs. The 7th was next tasked to fill the vacuum left by the departing divisions and sent undermanned units throughout Japan to secure the former occupation units’ areas. This made any form of unit training impossible. Individual replacements continued to be drawn from the division and its strength fell to 5,000, as did morale.
7th Marines’ machine gunners board a transport at Kobe, Japan bound for Inch’on. They are armed with .30 cal M1919A4 light machine guns, and their uniforms and equipment were the same as those worn by their comrades in World War II. (USMC)
On July 4 it was decided to employ the 7th for an amphibious operation and it was slowly built up with a target date of August 15. Replacements filtered in and three cadre battalions (officers, NCOs, specialists) were assigned from the 3d InfDiv in the States, with the intent of filling them with replacements; 20 percent of the replacements from the States were ordered to the 7th InfDiv and 30 percent on August 10.
In August the division concentrated in a training area near Yokohama and was promised much in the way of replacements and equipment, but received little. Troops continued to draw off to Pusan. The division now possessed 8,800 troops, less than half its authorized strength of 18,800. The 7th was relieved of occupation duties on July 26. Between August 23 and September 3 all infantry replacements from the States were sent to the 7th and all artillery replacements to the 8th, 5,800 in all. This of course denied replacements to the divisions defending Pusan.
On August 18, less than a month from D-Day, the division was informed that 8,637 replacements were arriving in Yokohama. Organizing transportation, the commander rushed to the port to find completely untrained and often unfit Korean recruits press-ganged off the streets of Pusan. They required delousing, uniforms, equipment, and weapons. They were to be outfitted, trained, and integrated into American units. The language barrier was insurmountable and there were many morale and cultural issues. These Korean Augmentation to the US Army personnel (KATUSA – pronounced “ka-to-sa”) were to be incorporated into US units. About 100 were assigned to each rifle company and artillery battery, meaning there were more Koreans than Americans in the units. The 32d Infantry, the division’s main participant in the battle, contained 3,110 Americans and 1,802 Koreans. Training continued, but there were serious concerns with regard to the rebuilt division’s readiness. To replace the 7th as the FECOM Reserve, the 3d InfDiv arrived on September 16, the day after the Inch’on landing. Including attachments, the 7th deployed with 24,845 troops and was only 1,400 men short.
MacArthur wanted one other army unit for Operation Chromite. He requested an RCT from the 82d AbnDiv. The JCS, though, refused to tap the 82d, the nation’s only General Reserve unit. The 187th ARCT (Airborne Regimental Combat Team) from the 11th AbnDiv could be sent, but had to be built up and trained. With the prohibition on airlifting units to Korea, the unit would have to be sea-lifted and would not arrive until October 18.
Geographic and hydrographic characteristics would make the Inch’on landing one of the most difficult ever attempted. Inch’on is situated on the upper west coast of the Republic of Korea, 20 miles west-southwest of Seoul and 30 miles south of the 38th Parallel. Known as Jinsing to the Japanese, and with a prewar population of 250,000, Inch’on sat on a blunt two square mile short peninsula. It was an industrial city and had long served as Seoul’s seaport. The coastal terrain was mostly flat, but several small hills rose within the city, the most notable being Cemetery Hill (130ft) and British Consulate Hill (150ft), Hill 117 (384ft), and a forested ridge about 700 yards square, some 500–700yd inland, Observatory Hill (200ft). The inland base of the peninsula was hilly, and the hills rose farther inland until disappearing into the large plain of the Kimpo Peninsula which stretched north with the Yellow Sea on its west side and the Han River estuary on its east.
Sowolmi-do is in the center of this picture with its causeway to the left connecting it to Wolmi-do. In the upper right, edging by black smoke, is the Outer Tidal Basin. The smaller Inner Tidal Basin lies beneath the smoke. (USN)
The hills on the northwest side of Seoul were higher and more rugged. The NKs established their main line of resistance across these hills and ridges. In the foreground is a railroad embankment. (USMC)
The Inch’on Railroad Station still burns on D+1 from the naval bombardment it received the day before. (USMC)
Wolmi-do (Moon Tip Island) dominated the harbor, being 800yd west off the end of the Inch’on peninsula. The roughly triangular-shaped island measured some 1,000yd each side. Most of the island was occupied by a steep-sided, brush-covered 351-ft hill, known as Radio Hill because of the commercial radio antenna. The island’s northeast side and northern tip was occupied by an industrial area. It was also a fishing boat base and tourist attraction with a swimming pool, shops, and restaurants. A 800-yd causeway connected Wolmi-do with the mainland. Another 750-yd causeway jutting south from the west corner was connected to Sowolmi-do, a rocky, hill-like islet with a lighthouse. The two 12-yd wide causeways served as breakwaters enclosing the north and west sides of Inch’on Harbor (Inch’on Hang). The northeast side of the harbor was edged with a waterfront of piers, warehouses, and port facilities. Stone and concrete seawalls (up to 15ft high at high tide) faced the city and port waterfronts, as well as Wolmi-do itself. On the southeast side of the harbor was a large tidal basin, and thrusting out 1,400yd from it was a stone breakwater that defined the south side of the harbor. Port facilities also lined the shore outside the main harbor to the north. On the south side were the Inner and Outer Tidal Basins providing a haven for ships when receding tides would leave them stranded on the mud flats. Near the base of both sides of the peninsula were large salt evaporation pans. The city’s streets were a chaotic maze and many buildings were of concrete and masonry construction.
To reach Inch’on from the Yellow Sea, either the western Flying Fish Channel (So Sudo) or the near-shore East Channel (Tong Sudo) had to be negotiated from the southwest, winding through scattered islands, mud banks, rock outcroppings, and strong currents; both routes were 50 miles long and the channels 36–60ft deep. The East Channel ran between Yongdungpo-do and Taebu-do, 15 miles south of Inch’on (Taebu-do was occupied by North Korea). Flying Fish Channel ran north of Yong-hong-do. The two channels converged at Palmi-do, an islet 10 miles from Inch’on. To make matters worse, the fleet would have to make this dangerous approach in darkness to take advantage of the morning high tide. The Flying Fish Channel was selected with fewer hazards. There was no maneuver space in the 2,000–3,500yd channel between Inch’on and Yongjong-do and its fringing 6,000yd wide mud flats to the northwest if the invasion fleet was attacked by air, and even less when the tide ebbed.
Once Inch’on was secured the marines would have to cover 20 miles of ground to reach Seoul on the Inch’on–Seoul Highway, which had a railroad running parallel along it. The ground was comparatively flat, but there were numerous scattered hills affording the North Koreans defensive positions. The low, round-topped hills and ridges had gradually sloped sides and were either bare or partly covered by brush or pine trees. However, there were numerous gullies on the flat ground and hillsides and a few wooded areas offering cover. The level ground consisted of cultivated fields and rice paddies cut by small streams. The area had also been used as a Japanese training ground and was dotted with concrete pillboxes and obstacles, which the North Koreans employed. Ascom City3, Sosa, and Yongdungp’o lay astride the route. The latter, an industrial suburb, sat on the south side of the Han River opposite Seoul. Between the town and river was a vast sandy flat on which the small Seoul airstrip sat. The main airfield in the area, though, was Kimpo to the northwest of Yongdungp’o and south of the river. The highway and railroad bridges connecting Yongdungp’o and Seoul had been destroyed before the North Koreans took the city. From Yongdungp’o a highway ran south to Suwon and Osan. This was the main North Korean supply route to Pusan and it would also be one of the routes Eighth US Army would take north once it broke out. Ferry crossings were located at Haengju northwest of Seoul, and Sinsa-ri on the city’s southeast side, but all the ferries had been destroyed.
The north-central section of Seoul with Government House, the capitol, in the upper center. To the right can be seen the Duksoo Imperial Palace. The hills on the city’s north side are just off the top of the photograph. (USA)
Marines move cautiously up a side street in a residential neighborhood. Most Korean homes are surrounded by stout masonry walls. The marine in the foreground carries 81mm mortar projectile tubes on his back. (USMC)
The northwest-flowing Han presented an obstacle on the route to Seoul, but the river was slow and only a few hundred yards wide. Its depth though, even far inland, was affected by Yellow Sea tides. While it separated regiments of the 1st MarDiv for part of the operation, the NK never took full advantage of it as a barrier. The marine and army amphibious tractors (amtracs) were invaluable in the crossing of this and other water obstacles.
In 1950 Seoul (Keijo to the Japanese, and still identified as such on maps) was the fifth largest city in Asia, with a population of 680,000. Situated on a bend on the north bank of the Han, Seoul was a relatively modern city with many multistorey concrete and masonry businesses, commercial buildings, and apartment blocks. Among these were the city hall, large school complexes, churches, hotels, embassies, Yongsan Railroad Station, Sodaeman Prison, and the ancient Duksoo Imperial Palace. The Japanese had built Government House, the largest concrete building in Asia, in front of the Imperial Palace grounds to obscure it. Government House had served as the Japanese colonial capitol, the Republic of Korea capitol building, and a North Korean strongpoint. In the sprawling suburbs were wooden and masonry dwellings. Hills and ridges were scattered through Seoul and defined its limits. On the north and northwest sides it was overlooked by forested hills. The streets were broad and several railroads ran through the city. Main highways ran northwest to Kaesong, northeast to Uijongbu, and southeast to Ch’ungiu.
The hydrographic characteristics of the Inch’on area were a major issue with invasion planners and higher headquarters. Inch’on experienced the second most drastic tidal changes in the world4. At the time of the landing the spring tide would be higher than normal, with 23–33ft tides. A 25ft tide was necessary for small landing craft to reach the seawall. On September 15 there would be a 31.5ft tide, higher than normal. This would provide the 29ft of water required by the Landing Ships, Tank (LST). Only on a few days in the middle of September and October would sufficient depths be available. The morning high tide would be at 0659hrs followed by a low tide that saw the bay empty of water tearing out at 6–7 knots. Evening high tide would be at 1919hrs with a flood rate of 3 knots. When the tide was out any ships remaining in the nearshore bay would be stranded on mud flats, although ships in the channel remained afloat. In case they were stranded, ships were armed with grenades and submachine guns to guard against North Korean infantry attacks across the mud.
Day temperatures were warm, upper 80°F with frequent rain squalls and the skies partly overcast on D-Day. Nights were cool in the low 70°F range. Nightfall was at 1900hrs. The varied terrain would be a challenge to the marines and soldiers involved in this campaign. They would conduct an amphibious landing, fight in large modern cities and crude peasant villages against a well-entrenched enemy; they had to carry out multiple river crossings and face armor attacks on hills, ridges, open plains, and rice paddies.
1 The UN recognized the ROK on December 15, but it was not admitted to the UN until 1991, as was North Korea.
2 A marine or army RCT consisted of a core infantry regiment, 105mm artillery battalion, engineer and medical companies, usually a tank element, other combat support elements as necessary, and small service support elements.
3 Ascom City’s native name is Taejong-ni. During the US occupation it was developed as the Army Service Command base resulting in “Ascom,” the common name used in official histories.
4 The most drastic tidal changes are found in the Bay of Fundy, Nova Scotia.