Ben Chifley, Australian engineer and politician, 16th Prime Minister of Australia (d. 1951)
Joseph Benedict Chifley (; 22 September 1885 – 13 June 1951) was an Australian politician who served as the 16th prime minister of Australia from 1945 to 1949. He held office as the leader of the Australian Labor Party (ALP).

Chifley was born in Bathurst, New South Wales. He joined the state railways after leaving school, eventually qualifying as an engine driver. He was prominent in the trade union movement before entering politics, and was also a director of The National Advocate. After several previous unsuccessful candidacies, Chifley was elected to parliament in 1928. In 1931, he was appointed Minister for Defence in the government of James Scullin. He served in cabinet for less than a year before losing his seat at the 1931 election, which saw the government suffer a wipeout loss.

After his electoral defeat, Chifley remained involved in politics as a party official, siding with the federal Labor leadership against the Lang Labor faction. He served on a royal commission into the banking system in 1935, and in 1940 became a senior public servant in the Department of Munitions. Chifley was re-elected to parliament later that year, on his third attempt since 1931. He was appointed Treasurer in the new Curtin Government in 1941, as one of the few Labor MPs with previous ministerial experience. The following year Chifley was additionally made Minister for Postwar Reconstruction, making him one of the most powerful members of the government. He became prime minister following Curtin's death in office in 1945, defeating caretaker prime minister Frank Forde in a leadership ballot.

At the 1946 election, Chifley was re-elected with a slightly reduced majority – the first time that an incumbent Labor government had won re-election. The war had ended a month after he took office, and over the following four years his government embarked on an ambitious program of social reforms and nation-building schemes. These included the expansion of the welfare state, a large-scale immigration program, and the establishment of the Australian National University, ASIO, and the Snowy Mountains Scheme. Some of the new legislation was successfully challenged in the High Court, and as a result the constitution was amended to give the federal government extended powers over social services.

Some of Chifley's more interventionist economic policies were poorly received by Australian business, particularly an attempt to nationalise banks. His government was defeated at the 1949 election, which brought Robert Menzies' Liberal Party to power for the first time. He stayed on as Leader of the Opposition until his death, which came a few months after the 1951 election; Labor did not return to government until 1972. For his contributions to post-war prosperity, Chifley is often regarded as one of Australia's greatest prime ministers. He is held in particularly high regard by the Labor Party, with his "light on the hill" speech seen as seminal in both the history of the party and the broader Australian labour movement.