Tecumseh joined British Major-General Sir Isaac Brock in the siege of Detroit, and forced its surrender in August 1812. As Brock advanced to a point just out of range of Detroit's guns, Tecumseh had his approximately four hundred warriors parade from a nearby wood and circle around to repeat the maneuver, making it appear that there were many more than was actually the case. The fort commander, Brigadier General William Hull, surrendered in fear of a massacre should he refuse. The victory was of a great strategic value to the invaders.