Prime Minister of the United Kingdom retirement from the Commons, which elevates the individual to the House of Lords. Formerly, the peerage bestowed was usually an earldom, with Churchill offered a dukedom. From the 1960s onward, life peerages were preferred, although in 1984 Harold Macmillan was created Earl of Stockton. Sir Alec Douglas-Home, Harold Wilson, James Callaghan and Margaret Thatcher accepted life peerages, although Douglas-Home had previously disclaimed his hereditary title as Earl of Home. Edward Heath did not accept a peerage of any kind and nor have any of the Prime Ministers to retire since 1990; although Heath and Major were later appointed as Knights
Prime minister could command the loyalty of the Commons was increasingly necessary. The long tenure of the wartime prime minister William Pitt the Younger (1783–1801), combined with the mental illness of George III, consolidated the power of the post. The title was first referred to on government documents during the administration of Benjamin Disraeli but did not appear in the formal British Order of precedence until 1905. The prestige of British institutions in the 19th century and the growth of the British Empire saw the British model of cabinet government, headed by a prime minister, widely copied, both in other European countries