The UN Forces September 1950 counteroffensive was a large-scale offensive by United Nations Command (UN) forces against North Korean forces commencing on 23 September 1950.
Following the UN counterattack at Inchon on 15 September, on 16 September UN forces within the Pusan Perimeter broke out of the perimeter, driving back the North Koreans and moved north linking up with the UN forces coming from Inchon near Osan on 27 September.
Background
By 23 September the Korean People's Army (KPA) was everywhere in retreat from the Pusan Perimeter. US Eighth Army, motorized and led by armored spearheads, was ready to sweep forward along the main axes of advance. On 22 September Eighth Army commander General Walton Walker issued his order for the pursuit. The Eighth Army order stated: Enemy resistance has deteriorated along the Eighth Army front permitting the assumption of a general offensive from present positions. In view of this situation it is mandatory that all efforts be directed toward the destruction of the enemy by effecting deep penetrations, fully exploiting enemy weaknesses, and through the conduct of enveloping or encircling maneuver get astride enemy lines of withdrawal to cut his attempted retreat and destroy him.
The order directed a full-scale offensive: US I Corps was to continue to make the main effort along the Taegu-Kumch'on-Taejon-Suwon axis and to effect a linkup with X Corps coming from Inchon; the US 2nd Infantry Division was to launch an unlimited objective attack along the Hyopch'on-Koch'ang-Anui-Chonju-Kanggyong () axis; the 25th Infantry Division on the army's southern flank was to seize Chinju and be ready to attack west or northwest on army order; and the Republic of Korea Army (ROK) in the east was to destroy the KPA in its zone by deep penetrations and enveloping maneuvers. An important section of the Eighth Army order and a key to the contemplated operation stated, "Commanders will advance where necessary without regard to lateral security." Later in the day, Eighth Army issued radio orders making IX Corps, under General John B. Coulter, operational at 14:00, 23 September and attaching the US 2nd and 25th Infantry Divisions to it. This order charged IX Corps with the responsibility of carrying out the missions previously assigned to the 2nd and 25th Divisions. In preparing for the pursuit, Eighth Army moved its headquarters from Pusan back to Taegu, reopening there at 14:00, 23 September.
The UN forces around the Pusan Perimeter at this time numbered almost 160,000 men, of whom more than 76,000 were in Eighth Army and about 75,000 in the ROK. UN reinforcements had begun arriving in Korea by this time. On 19 September the Philippine 10th Infantry Battalion Combat Team began unloading at Pusan, and on 22 September the 65th Regimental Combat Team started unloading there. The next day Swedish Red Cross Field Hospital personnel arrived at Pusan. On the 19th, the Far East Command deactivated the Pusan Logistical Command and reconstituted it as the 2nd Logistical Command, its mission of logistical support unchanged.
Offensive
The 25th Division crosses southwest Korea
On 23 September General Coulter, in a meeting with General Walker at the 25th Division command post, requested authority to change the division's axis of attack from southwest to west and northwest. He thought this would permit better co-ordination with the 2nd Division to the north. Walker told Coulter he could alter the division boundaries within IX Corps so long as he did not change the Corps' boundaries. The change chiefly concerned the 27th Infantry Regiment which now had to move from the 25th Division's south flank to its north flank. 25th Division commander General William B. Kean formed a special task force under Capt. Charles J. Torman, commanding officer of the 25th Reconnaissance Company, which moved through the 27th Infantry on the southern coastal road at Paedun-ni () the evening of the 23rd. The 27th Regiment then began its move from there to the division's north flank at Chungam-ni () . The 27th Infantry was to establish a bridgehead across the Nam River and attack through Uiryong to Chinju.
On the morning of 24 September Task Force Torman attacked along the coastal road toward Chinju. North of Sach'on the task force engaged and dispersed about 200 KPA soldiers of the 3rd Battalion, 104th Security Regiment. By evening it had seized the high ground at the road juncture south of Chinju. The next morning the task force moved up to the Nam River bridge which crossed into Chinju. In doing so one of the tanks hit a mine and fragments from the explosion seriously wounded Captain Torman, who had to be evacuated.
