The Queen's 13 prime ministers during her reign
Theresa May's appointment as prime minister makes her the 13th PM to serve Queen Elizabeth II, since her coronation in 1952.
Winston Churchill
The UK's wartime hero prime minister Winston Churchill was already in office at the time the Queen succeeded her father in 1952.
Anthony Eden
Taking over from his Tory colleague, Eden was at the helm for the 1956 Suez Crisis, which has been viewed as the biggest British foreign policy blunder of modern times. He resigned shortly afterwards.
Harold Macmillan
Conservative prime minister from 1957-1963.
Alec Douglas-Home
Other than current prime minister Theresa May, Conservative Douglas-Home served Queen Elizabeth for the shortest period of time out of any prime minister. He lasted just under a year after coming into office in October 1963.
Harold Wilson
The first Labour party prime minister in the Queen's reign, Wilson served two terms in office: 1964 to 1970 and 1974 to 1976.
Edward Heath
'Ted' Heath won 10 Downing Street from his Labour rival Harold Wilson in 1970, before being defeated by Wilson in 1974.
James Callaghan
Most famous for being in office during the 'winter of discontent', where the Labour leader clashed with unions leading to widespread strikes.
Margaret Thatcher
Margaret Thatcher won a general election against Labour's Callaghan - an election called following a vote of no confidence in the House of Commons which Callaghan lost by one vote. Thatcher was in office from 1979-1990.
John Major
Conservative prime minister from 1990-1997.
Tony Blair
Tony Blair took back the reigns of power for Labour in a landslide general election victory in 1997, serving as prime minister for a decade - the longest serving Labour prime minister.
Gordon Brown
Tony Blair stepped aside with his long-serving Chancellor Gordon Brown taking over as prime minister in 2007.
David Cameron
David Cameron, who visited the Queen today to officially resign as prime minister, was the youngest serving prime minister in the Queen's reign.
Theresa May
Lucky for some, Theresa May has become the 13th prime minister to serve the Queen.