The War of 1812 was a war between the United States and the United Kingdom. The countries at war included the United States, the United Kingdom, and some of the United Kingdom's colonies: Upper and Lower Canada (now Ontario and Quebec, respectively), Nova Scotia, and Bermuda. During this war, 2260 American and 1600 British troops died.

This war had several causes: the United Kingdom was warring with France, and wanted to keep the United States from trading hemp with France; the forced conscripting of Americans into the British navy; general British control on American trade; alleged British military aid for Americans Indians defending themselves against American settlers; and American desire to expand territory.

The Americans were not successful in the beginning of the War of 1812 because their repeated attempts to cross into Canada were blocked by General Issac Brock. The majority of General Brock's army consisted of local militias and American Indians who were allied with the British. The American army also consisted of local militias, but the militia members often refused to serve or had incompetent leaders, and the Americans also suffered from a lack of financial resources and many logistical problems. In addition, New England refused to provide troops or money for the war effort.

The British had plenty of money and superior logistical arrangements, but their concurrent war with France was deemed more important. Because of this, for the first two years of the War of 1812, the British took a defensive approach. In 1814, the war with France ended and the British sent armies to invade the US, but the Americans had finally adapted to fighting the British and devised better ways to solve logistical problems.

Although a large portion of the east coast was blockaded by the Royal Navy throughout the war, trade remained open through New England because of trade relationships with Britain and Canada. This blockade was extremely damaging to agricultural exports from the United States, but was good for manufacturing, as Americans had to rely on themselves for the production of goods.

Although the Americans attempted to defend its ports with small gunboats, this strategy was a failure due to British naval superiority. One of the more famous battles of the War of 1812 was a series of attacks on Chesapeake Bay, which ended in the Burning of Washington, during which the White House and the Capitol were burned down. The Americans managed some success with using hired mercenaries, or privateers, to attack British merchant ships. They also won control of Lake Erie, which served to keep western Ontario in check. American control of Lake Champlain allowed them to repel a British invading force in 1814.

In 1814, the British and Americans agreed to peace, returning the national boundaries to their prewar locations. In January of 1815, they signed the Treaty of Ghent, ending the War of 1812. In retrospect, this war united both the Canadians and the Americans much more strongly than they had been before the war.