The Battle of Chongju (29–30 October 1950) took place during the United Nations (UN) offensive towards the Yalu River, which followed the North Korean invasion of South Korea at the start of the Korean War. The battle was fought between Australian forces from 3rd Battalion, Royal Australian Regiment (3 RAR) and the 17th Tank Brigade of the Korean People's Army for control of Chongju, North Korea and the surrounding area. After detecting a strong North Korean armoured force equipped with T-34 tanks and SU-76 self-propelled guns on a thickly wooded ridgeline astride the line of advance, the Australians launched a series of company attacks with American M4 Sherman tanks and aircraft in support.