Orphaned at age 11, George Gordon (who added his deceased first wife's family name to his own surname in 1818) was reared by his guardians, the politicians William Pitt the Younger and Henry Dundas (afterward Viscount Melville), and inherited the earldom and associated titles from his grandfather in 1801. In 1813 he was appointed special ambassador to Austria. He was a central figure in European diplomacy at that time, helping to form the coalition that defeated Napoleon I. In 1814, after signing the Treaty of Paris on behalf of his king, he was created Viscount Gordon of Aberdeen in the peerage of the United Kingdom. In the government of the Duke of Wellington, he was chancellor of the duchy of Lancaster (January–June 1828) and foreign secretary (June 1828–November 1830), while in the brief first administration of Sir Robert Peel (November 1834–April 1, 1835), he was secretary for war and the colonies. As foreign secretary again (September 1841–July 1846) in Peel's second government, Aberdeen settled long-standing disputes over the eastern and western boundaries between Canada and the United States, by the Webster-Ashburton Treaty (1842) and the Oregon Treaty (1846).

On Dec. 28, 1852, Aberdeen formed a coalition Cabinet of Peelites (of whom he had been acknowledged leader after Peel's death in 1850), Whigs, and a Radical. In 1853, as his ministry reluctantly neared war with Russia over conflicts of interest in the Middle East, his indecision hampered the peacekeeping efforts of his foreign secretary, the 4th Earl of Clarendon. War became inevitable after Aberdeen and Clarendon sent the British fleet to Constantinople (September 23) and then, three months later, into the Black Sea. Both Great Britain and France declared war against Russia on March 28, 1854. Although he was ill-informed by the British generals in the Crimean War, Aberdeen was constitutionally responsible for their mistakes, and he resigned on Jan. 29, 1855.