General Sir Robert Abercromby GCB (1740–1827), the youngest brother of Sir Ralph Abercromby, was a general in the army, a knight of the Bath, and at one period the Governor of Bombay and Commander-in-Chief of the Bombay Army and then Commander-in-Chief, India.
Abercromby served in the French and Indian War, and was promoted captain in 1761. In 1773, he was promoted to lieutenant colonel of the 37th Regiment of Foot. During the American Revolutionary War, he fought at the Battle of Long Island, the Battle of Brandywine, the Battle of Germantown, the Battle of Crooked Billet, the Battle of Monmouth and at the sieges of Charleston and Yorktown, where he commanded the left wing of the British forces. He commanded a battalion of light infantry for most of the war. After the war, he was promoted to colonel. Abercromby served in India from 1790–1797, where he was Governor of Bombay and Commander-in-Chief of the Bombay Army and then, from 1793, Commander-in-Chief, India.
He was promoted lieutenant-general in 1797, elected M.P. for the county of Clackmannan in the place of his brother Ralph in 1798, was made governor of Edinburgh Castle in 1801 – a post he held until his death -, and a general in 1802. His increasing blindness made it impossible for him ever again to take active service, and obliged him to resign his seat in parliament in 1802.
Abercromby’s niece married James Alexander Haldane, and Abercromby subsequently bought the estate of Airthrey, Stirlingshire from J. A. Haldane’s brother Robert Haldane, who was selling his estates to take up missionary work in India. Sir Robert died at Airthrey in November 1827: aged 87, he was the oldest general in the British army. He was succeeded by his nephew, Lord Abercromby, the son of his elder brother, Sir Ralph.