The Battle of Kapyong, also known as the Battle of Jiaping, was fought during the Korean War between United Nations Command (UN) forces—primarily Canadian, Australian, and New Zealand—and the 118th and 60th Divisions of the Chinese People's Volunteer Army (PVA). The fighting occurred during the Chinese Spring Offensive and saw the 27th British Commonwealth Brigade establish blocking positions in the Kapyong Valley, on a key route south to the capital, Seoul. The two forward battalions—the 3rd Battalion, Royal Australian Regiment and 2nd Battalion, Princess Patricia's Canadian Light Infantry, both battalions consisting of about 700 men each—were supported by guns from the 16th Field Regiment of the Royal Regiment of New Zealand Artillery along with two companies of US mortars, fifteen Sherman tanks from US 72nd Heavy Tank Battalion, two companies of the US 74th Engineer Combat Battalion and 1st Battalion, Middlesex Regiment. These forces occupied positions astride the valley with hastily developed defences. As thousands of soldiers from the Republic of Korea Army (ROK) began to withdraw through the valley, the PVA infiltrated the brigade position under the cover of darkness, and assaulted the 3 RAR on Hill 504 during the evening and into the following day. Five companies of the US and UK forces attached to 27th Brigade fled the battlefield without orders, expecting an imminent PVA breakthrough at the Kapyong Valley.

The 27th Infantry Brigade was an infantry brigade of the British Army that saw service in the First World War, the Second World War, and the Korean War. In Korea, the brigade was known as 27th British Commonwealth Brigade due to the addition of Canadian, Australian, New Zealand and Indian units.