After the Americans launched an invasion in July 1812, the war raged back and forth along the border of Upper Canada, on land as well as on the waters of the Great Lakes. The British succeeded in capturing Detroit in July, and again in October. On July 12, US General William Hull invaded Canada at Sandwich (later known as Windsor). The invasion was quickly halted and Hull withdrew, giving General Isaac Brock the excuse he needed to abandon his previous orders and advance on Detroit, securing Shawnee chief Tecumseh's aid to do so. At this point, even with his aboriginal allies, Brock was outnumbered approximately two to one. However, Brock had gauged Hull as a timid man, and particularly as being afraid of Tecumseh's confederacy; he was thus able to convince Hull to surrender. The defeat of Detroit was utter and complete. A major American thrust across the Niagara frontier was defeated at the Battle of Queenston Heights, where Sir Isaac Brock lost his life.