George Hamilton-Gordon, 4th Earl of Aberdeen, Scottish politician, Prime Minister of the United Kingdom (died 1860)

George Hamilton-Gordon, 4th Earl of Aberdeen, styled Lord Haddo from 1791 to 1801, was a British statesman, diplomat and landowner, successively a Tory, Conservative and Peelite politician and specialist in foreign affairs. He served as Prime Minister from 1852 until 1855 in a coalition between the Whigs and Peelites, with Radical and Irish support. The Aberdeen ministry was filled with powerful and talented politicians, whom Aberdeen was largely unable to control and direct. Despite his efforts to avoid this happening, his ministry took Britain into the Crimean War, and fell when the war's conduct became unpopular. Subsequently, Aberdeen retired from politics.

The prime minister of the United Kingdom is the head of government of the United Kingdom. The prime minister advises the sovereign on the exercise of much of the royal prerogative, chairs the Cabinet, and selects its ministers. Modern prime ministers hold office by virtue of their ability to command the confidence of the House of Commons, so they are invariably members of Parliament.