Ngo was his family name. The French brought Catholicism with them to Vietnam, and the Ngo family was Catholic, the Catholics remaining no more than ten percent of the population. Ngo Dinh Diem was appointed Prime Minister by France's puppet king, Bao Dai. Then he benefited from a referendum held on October 23, 1955, that removed Bao Dai and declared the southern half of Vietnam a republic, making Diem the south's chief of state. The referendum has been described as a fraud. At polling places Diem's troops assaulted those thought to be voting to maintain the monarchy. Diem claimed more votes than there were registered voters. And he stayed in power by refusing to hold the nationwide elections that had been agreed to by the French and Vietnamese Communists at Geneva. Diem's rule was authoritarian and hostile to Buddhists. When he was overthrown in 1963 people in Saigon celebrated in the streets, cheering the army and bedecking their tanks with flowers.