The siege of Fort Sackville, also known as the siege of Fort Vincennes or the Battle of Vincennes, was an American Revolutionary War frontier battle fought in present-day Vincennes, Indiana. In February 1779, an American militia led by Lieutenant Colonel George Rogers Clark defeated the British garrison of Fort Sackville commanded by Lieutenant Governor Henry Hamilton. Clark surprised the fort after a gruelling march from Kaskaskia, and following the execution of four Odawa captives, forced Hamilton's surrender.