As the country prepared for yet another war with Britain, the United States suffered from internal divisions. While the South and West favored war, New York and New England opposed it because it interfered with their commerce. The declaration of war had been made with military preparations still far from complete. There were fewer than 7,000 regular soldiers, distributed in widely scattered posts along the coast, near the Canadian border and in the remote interior. These soldiers were to be supported by the undisciplined militia of the states.
Hostilities between the two countries began with an invasion of Canada, which, if properly timed and executed, would have brought united action against Montreal. But the entire campaign miscarried and ended with the British occupation of Detroit. The U.S. Navy, however, scored successes and restored confidence. In addition, American privateers, swarming the Atlantic, captured 500 British vessels during the fall and winter months of 1812 and 1813.
The campaign of 1813 centered on Lake Erie. General William Henry Harrison -- who would later become president -- led an army of militia, volunteers and regulars from Kentucky with the object of reconquering Detroit. On September 12, while he was still in upper Ohio, news reached him that Commodore Oliver Hazard Perry had annihilated the British fleet on Lake Erie. Harrison occupied Detroit and pushed into Canada, defeating the fleeing British and their Indian allies on the Thames River. The entire region now came under American control.
Another decisive turn in the war occurred a year later when Commodore Thomas Macdonough won a point-blank gun duel with a British flotilla on Lake Champlain in upper New York. Deprived of naval support, a British invasion force of 10,000 men retreated to Canada. At about the same time, the British fleet was harassing the Eastern seaboard with orders to "destroy and lay waste." On the night of August 24, 1814, an expeditionary force burst into Washington, D.C., home of the federal government, and left it in flames. President James Madison fled to Virginia.
As the war continued, British and American negotiators each demanded concessions from the other. The British envoys decided to concede, however, when they learned of Macdonough's victory on Lake Champlain. Urged by the Duke of Wellington to reach a settlement, and faced with the depletion of the British treasury due in large part to the heavy costs of the Napoleonic Wars, the negotiators for Great Britain accepted the Treaty of Ghent in December 1814. It provided for the cessation of hostilities, the restoration of conquests and a commission to settle boundary disputes. Unaware that a peace treaty had been signed, the two sides continued fighting in New Orleans, Louisiana. Led by General Andrew Jackson, the Americans scored the greatest land victory of the war.
While the British and Americans were negotiating a settlement, Federalist delegates selected by the legislatures of Massachusetts, Rhode Island, Connecticut, Vermont and New Hampshire gathered in Hartford, Connecticut, in a meeting that symbolized opposition to "Mr. Madison's war." New England had managed to trade with the enemy throughout the conflict, and some areas actually prospered from this commerce. Nevertheless, the Federalists claimed that the war was ruining the economy. Some delegates to the convention advocated secession from the Union, but the majority agreed on a series of constitutional amendments to limit Republican influence, including prohibiting embargoes lasting more than 60 days and forbidding successive presidents from the same state. By the time messengers from the Hartford Convention reached Washington, D.C., however, they found the war had ended. The Hartford Convention stamped the Federalists with a stigma of disloyalty from which they never recovered.