June 18 - The U.S. declares war on Britain, beginning the War of 1812. There are but 4,000 British troops in Canada. Sir George Prevost is Governor. Four Canadian battalions are assembled, and the Citadel at Quebec is guarded by the inhabitants.
October - Almost half of Vermont's Legislators regard war as needless and impolitic; but Vermont imposes a penalty of $1,000 for every unauthorized communication with Canadians.
October 13 - Stephen Van Renselaer's command is repulsed, on Queenston Heights by Gen. Sheaffe and Governor Brock, who is killed. Of the 10,000 under Van Renselaer, many were unwilling to invade, though willing to defend the United States.
Fighting on the same side as British militia and Mohawk Indians, a group of black soldiers helps force American invaders to retreat in the Battle of Queenston Heights.
The War of 1812 (in Britain, the American War of 1812 to 1815), was fought between the United States and the British Empire from 1812 to 1815, on land in North America and at sea.
The militia, called in to aid the regulars, objected to serving outside their home states, were not amenable to discipline and, as a rule, performed poorly in the presence of the enemy when outside of their home state.
The American Brigadier General William Hull invaded Canada on July 12, 1812 from Detroit, with an army mainly composed of militiamen, but turned back after his supply lines were threatened in the Battles of Brownstown and Monguagon.