The Prime Minister of the United Kingdom of Great Britain and Northern Ireland is the political leader of the United Kingdom and the leader of the executive branch of government. The Prime Minister is a Member of Parliament, and in his executive capacity, is accountable to Parliament. The post is generally acknowledged to have begun with Sir Robert Walpole on 4th April 1721 when he obtained the post of First Lord of the Treasury. The incumbent Prime Minister is Gordon Brown, who took over from Tony Blair on 27th June 2007.
10. Edward Heath Wikipedia

Edward Heath was Prime Minister from 19th June 1970-4th March 1974. His time was difficult, particularly with domestic problems in Northern Ireland and tremendous industrial unrest. One of his great triumphs was the 1973 Sunningdale Agreement, which while short-lived, was the first real attempt by a Prime Minister to put a stop to ‘The Troubles’ in Northern Ireland. However, what Heath is most remembered for is bringing the UK into the European Economic Community. He called an early election and after inconclusive results he resigned.
(Read the rest of this list…)