Prime Minister of the United Kingdom century as a convention of the constitution, the position of Leader of the Opposition was given statutory recognition in 1937 by the Ministers of the Crown Act. British Prime Ministers have never been elected directly by the public. A Prime Minister need not be a party leader; David Lloyd George was not a party leader during his service as prime Minister during World War I, and neither was Ramsay MacDonald from 1931 to 1935. Prime Ministers have taken office because they were members of either the Commons or Lords, and either inherited a majority in the Commons or won more
House of Commons of the United Kingdom a different one). By this second mechanism, the government of the United Kingdom can change without an intervening general election. Only four of the eight last Prime Ministers have attained office as the immediate result of a general election; the others have gained office upon the resignation of a Prime Minister of their own party. The latter four were Jim Callaghan, John Major, Gordon Brown and the current Prime Minister Theresa May; these four inherited the office from Harold Wilson, Margaret Thatcher, Tony Blair and David Cameron respectively. In such circumstances there may not even have been an internal party