Lê Quang Tung, loyalist head of the South Vietnam Special Forces, was executed in a U.S.-backed coup against president Ngô Đình Diệm following a period of religious unrest.

Colonel Lê Quang Tung was the commander of the Army of the Republic of Vietnam Special Forces under the command of Ngô Đình Nhu. Nhu was the brother of South Vietnam's president, Ngô Đình Diệm. A former servant of the Ngô family, Tung's military background was in security and counterespionage.

The Army of the Republic of Vietnam Special Forces were the elite military units of the Army of the Republic of Vietnam (ARVN). Following the establishment of the Republic of Vietnam in October 1955, the Special Forces were formed at Nha Trang in February 1956. During the rule of Ngô Đình Diệm, the Special Forces were run by his brother, Ngô Đình Nhu, until both were assassinated in November 1963 in a coup. The Special Forces were disbanded in 1975 when South Vietnam ceased to exist after the Fall of Saigon.

In November 1963, President Ngô Đình Diệm and the Personalist Labor Revolutionary Party of the Republic of Vietnam were deposed by a group of CIA-backed Army of the Republic of Vietnam officers who disagreed with Diệm's handling of the Buddhist crisis and the North Vietnamese and Viet Cong threat to South Vietnam. In South Vietnam, the coup was referred to as Cách mạng 1-11-63.

Ngô Đình Diệm was a South Vietnamese politician who was the final prime minister of the State of Vietnam (1954–1955) and later the first president of South Vietnam from 1955 until his capture and assassination during the CIA-backed 1963 coup d'état.