Nguyễn Chánh Thi ([ŋwiəŋ˨˦ c̻an˦ˀ˥ tʰi˧˥]; 23 February 1923 – 23 June 2007) was an officer in the Army of the Republic of Vietnam (ARVN). He is best known for being involved in frequent coups in the 1960s and wielding substantial influence as a key member of various juntas that ruled South Vietnam from 1964 until 1966, when he was overpowered by Republic of Vietnam Air Force chief and Prime Minister Nguyễn Cao Kỳ in a power struggle and exiled to the United States. Known for his flamboyant style and hostility to U.S. advice, Thi's ouster was supported by the American leadership, who backed Kỳ's pro-U.S. regime.