Aberdeen's career was dominated by foreign policy, but his experience did not prevent the slide towards the Crimean War. His personal life was marked by the loss of both parents by the time he was eleven, and of his first wife after only seven years of a happy marriage. His daughters died young, and his relations with his sons were difficult. Before his marriage he travelled extensively in Europe, including Greece, and he had a serious interest in the classical civilisations and their archaeology. On his return to Britain in 1805 he devoted much time and energy to improving conditions on his Scottish estates.
After the death of his wife in 1812 he became a diplomat, almost immediately being given the important embassy to Vienna while still in his twenties. His rise in politics was equally rapid and lucky, and "two accidents — Canning's death and Wellington's impulsive acceptance of the Canningite resignations" led to him becoming Foreign Secretary to the Duke of Wellington in 1828 despite "an almost ludicrous lack of official experience"; he had been a minister for less than six months. After holding the position for two years, followed by another cabinet role, by 1841 his experience led to his appointment as Foreign Secretary again under Robert Peel for a longer term. This was despite his being a "notoriously bad speaker", which mattered far less in the House of Lords, and having a "dour, awkward, occasionally sarcastic exterior". Nonetheless his Peelite colleague, later himself Prime Minister, William Ewart Gladstone, said of him that he was "the man in public life of all others whom I have loved. I say emphatically loved. I have loved others, but never like him".
Born in Edinburgh on 28 January 1784, he was the eldest son of George Gordon, Lord Haddo, son of George Gordon, 3rd Earl of Aberdeen. His mother was Charlotte, youngest daughter of William Baird of Newbyth. He lost his father in 1791 and his mother in 1795 and was brought up by Henry Dundas, 1st Viscount Melville and William Pitt the Younger. He was educated at Harrow, and St John's College, Cambridge, where he graduated with a Master of Arts in 1804. Before this, however, he had become Earl of Aberdeen on his grandfather's death in 1801, and had travelled all over Europe. On his return to England, he founded the Athenian Society. In 1805, he married Lady Catherine Elizabeth, daughter of John Hamilton, 1st Marquess of Abercorn.
In December 1805 Lord Aberdeen took his seat as a Tory Scottish representative peer in the House of Lords. In 1808, he was created a Knight of the Thistle. Following the death of his wife from tuberculosis in 1812 he joined the Foreign Service. He was appointed Ambassador Extraordinary and Minister Plenipotentiary to Austria, and signed the Treaty of Töplitz between Britain and Austria in Vienna in October 1813. In the company of the Austrian Emperor, Francis II he was an observer at the decisive Coalition victory of the Battle of Leipzig in October 1813; he had met Napoleon in his earlier travels. He became one of the central diplomatic figures in European diplomacy at this time, and he was one of the British representatives at the Congress of Châtillon in February 1814, and at the negotiations which led to the Treaty of Paris in May of that year.
Aberdeen was greatly affected by the aftermath of war which he witnessed at first hand. He wrote home: