Winston Churchill served as Prime Minister of the United Kingdom twice.
His first premiership began on 10 May 1940, when he replaced Neville Chamberlain during the crisis of the Second World War. Churchill led a national coalition through the struggle against Nazi Germany and remained prime minister until the Conservatives lost the 1945 general election to Clement Attlee’s Labour Party.
Churchill returned to office after the Conservatives won the 1951 general election. His second premiership lasted from 26 October 1951 to 5 April 1955, when he resigned because of declining health. Anthony Eden succeeded him.
The common mistake is to count Churchill’s wartime leadership and his later return as one continuous career, or to confuse his premierships with his several periods as a cabinet minister and Leader of the Opposition. He was also Conservative Party leader from 1940 to 1955, but that is a separate office.