The United States Army in 1812 was small, and state militias proved inadequate to fight well-trained veterans. Early campaigns were designed to take Canada, an appealing goal because of the abundance of land, the lucrative fur trade and problems with Indians. All the early Canadian campaigns were unsuccessful, however. General William Hull invaded Canada in July 1812 but was forced to surrender to British Major General Isaac Brock in Detroit. Brock then moved to the eastern end of Lake Erie where American General Stephen Van Rensselaer was attempting unsuccessfully to invade. A third attempt at invasion failed when General Henry Dearborn's New York militia troops refused to enter Canada.
In 1814, England planned a three-pronged attack on the United States: a march from Canada into the Hudson River Valley, an amphibious assault on the Chesapeake Bay region, and occupation of New Orleans. The decisive campaign was in New York State. General Sir George Prevost led a British force into New York and advanced to Plattsburg. Although he outnumbered the American garrison there, when American sailors under Commodore Thomas McDonough defeated the British on Lake Champlain, Prevost withdrew.
Meanwhile, British Admiral George Cockburn was conducting operations in the Chesapeake Bay area, raiding towns along the coast. In August 1814 he marched on the capital and handily defeated the American militia in the Battle of Bladensburg, Maryland. Dolley Madison saw to the saving of valuables, including a portrait of George Washington, even as James Madison was forced to flee the presidential mansion. British General Ross ate the dinner which had been prepared for the president, drank a toast to "Little Jemmy," and set fire to the building. The next day British troops burned many more buildings in Washington.
The British then advanced on Baltimore, but were unable to reduce Fort McHenry, which had been built following the American Revolution to protect the Baltimore harbor. British warships bombarded the fort for over 24 hours, but were unable to penetrate the harbor, which was also protected by chains and sunken ships. The strong stand at Fort McHenry led Francis Scott Key, who observed the bombardment through a long night as bursting shells illuminated the flag, to compose his famous anthem.