Senanayake, Don Stephen (sĕnənä`yəkə), 1884–1952, prime minister (1947–52) of Ceylon (later Sri Lanka). He entered politics in 1922 and became a prominent leader before founding the United National party (UNP) in 1946 and leading Ceylon to independence from Great Britain in 1948. He was as minister of agriculture and lands (1931–47) and leader of the council of state (1942–47). He died in office and was succeeded as prime minister by his son Dudley Shelton Senanayake, 1911–73, who had followed his father as minister of agriculture and lands (1947–52). Dudley Senanayake served three periods as a right-of-center prime minister (1952–53, 1960, 1965–70) and led the opposition UNP in 1960–65.