In Australia, a decades-long lingering mystery has been what happened to Prime Minister Harold Holt. A member of the Liberal Party of Australia (which, despite the name, is actually the country's primary conservative party), Holt had been Prime Minister during an eventful and controversial period in the 1960s before his disappearance towards the end of 1967.
Holt's first foray into national politics came when he unsuccessfully ran for the Australian House of Representatives in 1934 as a member of the United Australia Party, losing to former Prime Minister James Scullin. In his next attempt the following year, he was again unsuccessful. However, five months later in August, he won a by-election following the death of George Maxwell and finally became a member of the House of Representatives. Quickly, Holt rose through the ranks and became Minister in charge of Scientific and Industrial Research.
While still a member of the House of Representatives, Holt briefly served with the Australian Army during World War II. Following a government shake-up and the collapse of the United Australia Party, Holt joined the newly-created Liberal Party. Later posts Holt held include Minister for Labour and National Service, Minister for Immigration and Treasurer of Australia.
Early in 1966, Prime Minister Robert Menzies retired after a career of considerable length. Holt was chosen as his successor. In domestic policy, Holt's government took steps to abolish the White Australia policy and held a referendum that resulted in a more inclusive federal government with the Aboriginals. In foreign affairs, he was a staunch supporter of U.S. President Lyndon B. Johnson and the Vietnam War. In November of 1966, Holt led the Liberal Party and its coalition partner, the Country Party, to a landslide victory in the Australian federal election.
On December 17, 1967, Holt and a number of companions went to a favorite spot of his, Cheviot Beach in Victoria. Despite rough conditions, he decided to go out for a swim. His travelling companions eventually lost sight of him. Soon, a major police and military search and rescue operation was underway, to no avail. On December 19, the government declared that he was thought to be dead. A memorial service was held at St Paul's Anglican Cathedral in Melbourne on the 22nd. The attendees included Prince Charles, President Johnson and British Prime Minister Harold Wilson.
Several theories would be brought forward as attempts to explain the Prime Minister's sudden vanishing. So much, that it has been labeled a national myth. One outlandish theory includes Holt being a sort of double agent for the Chinese.
There is a more widely-accepted theory. Holt had been experience health problems. It was speculated that he was suffering from a heart condition. Additionally, he had been in a great deal of pain from a shoulder injury and had been prescribed high-power medications. The possible combination of a painful injury, a possible heart condition, the effects of potent medicine and the turbulent conditions may have been too much for Holt and he could have ultimately been overtaken.
The Australian Capital Territory suburb Holt is named after the Prime Minister, as is Naval Communication Station Harold E. Holt. In 1968, the United States Navy named a newly-commissioned vessel the USS Harold E. Holt in his honor, marking the first time an American warship was named after a foreign leader. The following year, a memorial plaque was installed on the seafloor near the location of Holt's disappearance. A perhaps less-dignified way a remembrance are the sayings in Australia 'do a Harold Holt' and 'do a Harry', referring to someone suddenly vanishing (usually from something like a room or a party, not in a dangerous situation).
Holt's disappearance also caused a transfer of political power. The new Prime Minister would be John McEwen, the Leader of Australia's other major conservative party, the Country Party (now the National Party of Australia) . While the two parties have been in a long-standing coalition and have essentially worked as one party, both while in power and in opposition, McEwen's tenure as Prime Minister is the last (and technically only) time to date that the coalition was headed by a member of the Country or National Party.