Nguyễn Cao Kỳ was a Vietnamese military officer and politician who served as the chief of the Republic of Vietnam Air Force in the 1960s, before leading the nation as the prime minister of South Vietnam in a military junta from 1965 to 1967. Then, until his retirement from politics in 1971, he served as vice president to bitter rival General Nguyễn Văn Thiệu, in a nominally civilian administration.
Born in northern Vietnam, Kỳ joined the Vietnamese National Army of the French-backed State of Vietnam and started as an infantry officer before the French sent him off for pilot training. After the French withdrew from Vietnam and the nation was partitioned, Kỳ moved up the ranks of the Republic of Vietnam Air Force to become its leader. In November 1963, Kỳ participated in the coup that deposed president Ngô Đình Diệm and resulted in Diệm's assassination.
In 1964 Kỳ became prominent in junta politics, regarded as part of a group of young, aggressive officers dubbed the "Young Turks". Over the next two years, there were repeated coup attempts, many of which were successful, and Kỳ was a key player in supporting or defeating them.