The Kingdom of Laos was a constitutional monarchy that served Laos beginning with its independence on 9 November 1953. The monarchy survived until December 1975, when its last king, Sisavang Vatthana, surrendered the throne to the Pathet Lao, who abolished the monarchy in favour of a Marxist–Leninist state called the Lao People's Democratic Republic, which has controlled Laos ever since.