James Ochoncar Forbes, 17th Lord Forbes (1765–1843), was a Scottish soldier and peer. He was the eldest son of James Forbes, 16th Baron Forbes, by Catherine, only daughter of Sir Robert Innes, baronet, of Orton. The lands of Forbes, Aberdeenshire, still in their possession, have been held by this family since the reign of William the Lion (1165–1214).
Forbes was born 17 March 1765. He entered the army as ensign in the Coldstream Guards 13 June 1781, became lieutenant and captain 21 April 1786, captain and lieutenant-colonel 23 August 1793, colonel 3 May 1796, major-general 29 April 1802, lieutenant-general 27 March 1808, and general 12 Aug. 1819. He served in Flanders with his distinguished regiment, and was present in the battles and sieges of Raismes, Famars, Dunkirk, Lincelles, Tournay, &c. He subsequently accompanied the Helder Expedition, and was present in nearly every action which took place in that campaign. He was appointed second in command of the troops in the Mediterranean in March 1808, and in the same year sailed for Sicily. He was colonel 3rd Garrison Battalion 1807–9, 94th Foot 14 April 1809, 54th Foot 23 September 1809, and 21st Foot 1 June 1816 till his death. He was also a knight in the Order of Saint Januarius.
Forbes succeeded his father in the title in 1804, and was chosen a representative peer in 1806. He married at Crailing, 2 June 1792, Elizabeth, eldest daughter and heiress of Walter Hunter, esq., of Polmood, in the county of Peebles, and Crailing, in the county of Roxburgh, by the Lady Caroline Mackenzie, fourth daughter of the Earl of Cromartie, by whom he had ten children.