Baltimore was a busy port and was thought by the British to harbor many of the privateers who were raiding British shipping

The British sent a fleet up the Potomac to block Washington's access to the water and to threaten the thriving ports of Georgetown and Alexandria, which are both close to Washington. The American defense forces were so intimidated by the fleet's mere presence that they abandoned Fort Warburton without firing a shot, and undefended Alexandria was forced to submit.

After many days of robbing city merchants of hundreds of tons of goods, the British moved their focus north to Baltimore in the hopes of dealing a crushing blow to the discouraged Americans. One of the facts about Baltimore in the War of 1812, Baltimore was a busy port and was thought by the British to harbor many of the privateers who were raiding British shipping. Vice-Admiral Sir Alexander Cochrane was to besiege Fort McHenry, which was the key military structure in Baltimore Harbor, while Ross was to launch a land attack at North Point.

Major General Samuel Smith, the state militia commander, had organized Baltimore's fortifications in advance.