Major-General Sir Isaac Brock KB (6 October 1769 – 13 October 1812) was a British Army officer and colonial administrator from Guernsey. He is best remembered for his victory at the siege of Detroit and his death at the Battle of Queenston Heights during the War of 1812.
Brock joined the army as an ensign in 1785. By 1797, he was a lieutenant colonel with the 49th Regiment of Foot. The regiment participated in the Anglo-Russian invasion of Holland in 1799 and in the 1801 naval expedition against Copenhagen. In 1802, the 49th Regiment was assigned to garrison duty in British North America. Despite facing desertions and near-mutinies, Brock successfully commanded his regiment in Upper Canada (part of present-day Ontario) for several years. He was promoted to colonel in 1805 and appointed brigadier general in 1808. In 1811 he was promoted to major general and given responsibility for defending Upper Canada against the threat of an American invasion. While many in Canada and Britain believed war could be averted, Brock began to ready the regulars and militia for what was to come. When the War of 1812 broke out, the populace was prepared, and quick victories at Fort Mackinac and Detroit temporarily thwarted American invasion attempts.