Harold Edward Holt, CH (5 August 1908 – 17 December 1967), was an Australian politician who served as the 17th Prime Minister of Australia, in office from 1966 until his presumed drowning death in 1967. He was the leader of the Liberal Party during that time.
Holt, born in Sydney, lived in Melbourne from 1920. He was the first prime minister born in the twentieth century, after the Federation of Australia. He studied law at the University of Melbourne and had his own legal practice, becoming, at twenty-seven years of age, the member for Fawkner in the House of Representatives at a 1935 by-election. A protégé of Robert Menzies, he was a minister in the 1939 United Australia Party government. He held a series of minor portfolios until the government's defeat in 1941. His tenure was interrupted by a brief stint in the Australian Army, which ended when he was recalled to cabinet following the deaths of three ministers in the 1940 Canberra air disaster. He joined the new Liberal Party upon its creation in 1945.
When the Liberals came to office in 1949, Holt became a senior figure in the new government. As Minister for Immigration (1949–56), he expanded the post-war immigration scheme and relaxed the White Australia policy for the first time. He was also influential as Minister for Labour and National Service (1949–58), where he handled several industrial relations disputes. Holt was elected deputy leader of the Liberal Party in 1956, and after the 1958 election replaced Arthur Fadden as Treasurer. He oversaw the creation of the Reserve Bank of Australia and the decimal Australian dollar, but was blamed for a credit crunch that almost cost the Coalition the 1961 election. However, the economy soon rebounded and Holt retained his place as Menzies' heir apparent.
Holt became prime minister in January 1966, elected unopposed as Liberal leader following Menzies' retirement. He fought a general election later that year, winning a landslide victory. The Holt Government continued the dismantling of the White Australia policy, amended the constitution to give the federal government responsibility for indigenous affairs, and took Australia out of the sterling area. Holt promoted greater engagement with Asia and the Pacific, and made visits to a number of East Asian countries. His government expanded Australia's involvement in the Vietnam War, and maintained close ties with the United States under President Lyndon B. Johnson. While visiting the White House, Holt proclaimed that he was "all the way with LBJ", a remark which was poorly received at home.
After just under two years in office, Holt disappeared while swimming at Cheviot Beach, Victoria, in rough conditions. He was presumed dead, although his body was never recovered; his disappearance spawned a number of conspiracy theories. Holt was the third Australian prime minister to die in office. He was succeeded by Country Party leader John McEwen on an interim basis and then by John Gorton. His death was commemorated in a number of ways, among them by the establishment of the Harold Holt Memorial Swimming Centre.