With the declaration of war in June 1812, planning began in Washington to strike north against British-held Canada. The prevailing thought in much of the United States was that the capture of Canada would be a simple and swift operation. This was supported by the fact the US possessed a population of around 7.5 million while Canada's numbered only 500,000. Of this smaller number, a large percentage was Americans who had moved north as well as the French population of Quebec. It was believed by the Madison Administration that many from these two groups would flock to the American flag once troops crossed the border. Indeed, former President Thomas Jefferson believed that securing Canada was a simple "matter of marching."
Despite these optimistic prognostications, the US military lacked the command structure to effectively execute an invasion. The small War Department, led by Secretary of War William Eustis, consisted of only eleven junior clerks. In addition, there was no clear scheme for how regular officers were to interact with their militia counterparts and whose rank took precedence. In determining a strategy for moving forward, most were in agreement that severing the St. Lawrence River would lead to the capitulation of Upper Canada (Ontario). The ideal method for achieving this was through the capture of Quebec. This idea was ultimately discarded as the city was heavily fortified and many remembered the failed campaign to take the city in 1775. In addition, any movement against Quebec would need to be launched from New England where support for the war was particularly weak.
Instead, President James Madison elected to approve a plan put forward by Major General Henry Dearborn. This called for a three-prong attack north with one moving up the Lake Champlain corridor to take Montreal while another advanced into Upper Canada by crossing the Niagara River between Lakes Ontario and Erie. A third thrust was to come in the west where American troops would advance east into Upper Canada from Detroit. This plan had the added advantage of having two offensives depart from strong War Hawk territory which was expected to be a strong source of troops. The hope was to have all three attacks commence at the same time with the goal of stretching the small number of British troops stationed in Canada. This coordination failed to occur (Map).
The troops for the westernmost offensive were in motion prior to the declaration of war. Departing from Urbana, OH, Brigadier General William Hull moved north towards Detroit with around 2,000 men. Reaching the Maumee River, he encountered the schooner Cuyahoga. Embarking his sick and wounded, Hull dispatched the schooner across Lake Erie to Detroit. Against the wishes of his staff who feared the ship's capture as it passed British Fort Malden, Hull had also placed the complete records of his army on board. By the time his force reached Detroit on July 5, he had learned that war had been declared. He also was informed that Cuyahoga had been captured. Hull's captured papers were forwarded to Major General Isaac Brock who was in command of British forces in Upper Canada. Undeterred, Hull crossed the Detroit River and issued a pompous declaration informing the people of Canada that they were free from British oppression.
Pressing down the east bank, he reached Fort Malden, but despite having a large numerical advantage, did not assault it. Problems soon arose for Hull when the anticipated support from the Canadian people failed to materialize and 200 of his Ohio militia refused to cross the river into Canada stating they would only fight on American territory. Growing concerned about his extended supply lines back to Ohio, he dispatched a force under Major Thomas Van Horn to meet a wagon train near the River Raisin. Moving south, they were attacked and driven back to Detroit by Native American warriors directed by the feared Shawnee leader Tecumseh. Compounding these difficulties, Hull soon learned that Fort Mackinac had surrendered on July 17. The loss of the fort gave the British control of the upper Great Lakes. As a result, he ordered the immediate evacuation of Fort Dearborn on Lake Michigan. Departing on August 15, the retreating garrison was quickly attacked by Native Americans led by the Potawatomi chief Black Bird and took heavy losses.
Believing his situation to be grave, Hull withdrew back across the Detroit River on August 8 amid rumors that Brock was advancing with a large force. The maneuver led to many of the militia leaders to ask for Hull's removal. Advancing to the Detroit River with 1,300 men (including 600 Native Americans), Brock utilized several ruses to convince Hull that his force was much larger. Holding his larger command at Fort Detroit, Hull remained inactive as Brock began a bombardment from the east bank of the river. On August 15, Brock called for Hull to surrender and implied that if the Americans declined and a battle resulted, he would not be able to control Tecumseh's men. Hull refused this demand but was shaken by the threat. The following day, after a shell hit the officers' mess, Hull, without consulting his officers, surrendered Fort Detroit and 2,493 men without a fight. In one quick campaign, the British had effectively destroyed the American defenses in the Northwest. The only victory occurred when young Captain Zachary Taylor succeeded in holding Fort Harrison on the night of September 4/5.