The Honorable Major General Alexander Leslie was a major general in the British Army during the American Revolutionary War. He was the commander of the British troops at the Battle of Harlem Heights. He replaced Cornwallis as commander in the South in 1782. In 1775, before the American War of Independence broke out, he led troops to Salem, Massachusetts looking for contraband weapons. His advance was delayed by a standoff at a bridge, during which the colonists removed the weapons he was looking for. His force was eventually allowed to proceed, but found nothing of consequence, and was received with hostility during the expedition. In 1776, Leslie was promoted to brigadier-general. He fought in the Battle of Long Island, the Landing at Kip's Bay, the Battle of White Plains and the Battle of Harlem Heights, the Battle of Princeton and the Siege of Charleston during the American War of Independence.

At Princeton, his nephew, Captain William Leslie was mortally wounded. In 1780, he was sent to the Chesapeake Bay by Sir Henry Clinton in order to "make a powerful diversion in favor by striking at the magazines then collecting by the enemy ... for supplying the army they were assembling to oppose him." He became major general in 1782 and was made Colonel of the 63rd (West Suffolk) Regiment of Foot the same year. He transferred in 1788 to be Colonel of the 9th (East Norfolk) Regiment of Foot to his death. On 27 December 1794, on his way back to Edinburgh, Leslie was seized with a dangerous illness, and died at Beechwood House, about three miles west of Edinburgh, on 27 December 1794.