Major-General Thomas Gordon (1788 – 20 April 1841) was a British army officer and historian. He is remembered for his role in the Greek War of Independence in the 1820s and 1830s and his History of the war published in 1833.
He was born at Cairness House to Charles Gordon of Buthlaw and Cairness in Lonmay, Aberdeenshire and his wife Christian, née Forbes of Ballogie. He was educated at Eton College and Brasenose College, Oxford.
From 1808 to 1810 he served in the Scots Greys. In May 1810 he left service in the British Army for travel and on 26 August was well received in Ioannina by Ali Pasha, local governor for the Ottoman Empire. Between 1810 and 1812, his travels included Athens, Constantinople, Thessaloniki as well as parts of Anatolia, Persia and Barbary.
In 1813, he served as a captain on the staff of the Russian Army, and in November 1813 was in the army of Count von Walmoden at Pretzer in Mecklenburg. Early in 1814, he returned to his seat of Cairness House until 1815 when he went abroad again to Constantinople, where he married Barbara Kana (afterwards Baroness de Sedaiges).