The Battle of Fort McHenry was a pivotal event during the War of 1812 between the United States and Great Britain

It took place between September 13 and 14, 1814, and is most famously associated with the creation of "The Star-Spangled Banner," the national anthem of the United States.

Background:
- War of 1812 Context: The War of 1812 was primarily fueled by ongoing tensions between the United States and Great Britain, including trade restrictions, impressment of American sailors into the British Navy, and British support for Native American attacks on American frontier settlements. By 1814, both sides were deeply entrenched in the conflict.
- Baltimore’s Strategic Importance: Baltimore, Maryland, was a vital port city and a center of American privateering, where privately-owned vessels were authorized to capture enemy ships. The British sought to capture Baltimore to disrupt American privateering efforts and deliver a psychological blow to the American war effort.

The Battle:
- British Intentions: Following their victory in Washington D.C., where they famously burned the White House and the Capitol, the British turned their attention to Baltimore. Their strategy involved both a naval bombardment of Fort McHenry, which defended the Baltimore harbor, and a land assault on the city.
- Defense of Fort McHenry: The fort was commanded by Major George Armistead and garrisoned by approximately 1,000 men. Anticipating the attack, Armistead prepared the fort by reinforcing its defenses and raising a large American flag—intended to be visible to the British.
- Naval Bombardment: The British fleet began its bombardment on the morning of September 13, 1814. The attack lasted for 25 hours, with the British firing between 1,500 and 1,800 cannonballs, rockets, and mortar shells at the fort.

Outcome:
- American Resilience: Despite the intense bombardment, Fort McHenry withstood the attack. The fort's defenders suffered relatively few casualties, and the British naval assault was unable to penetrate the harbor defenses, prompting the British to abandon their attack and withdraw.
- Francis Scott Key: During the battle, American lawyer and amateur poet Francis Scott Key was aboard a British ship negotiating the release of an American prisoner. Witnessing the fort's endurance and the sight of the large American flag still flying the next morning inspired him to pen a poem titled "Defence of Fort M'Henry.