War of 1812, 1812–1815

The United States declared war on the British Empire in 1812 for several reasons including: trade restrictions brought about by Britain's ongoing war with France, the impressment of American merchant sailors into the Royal Navy, British support of American Indian tribes, and possible American desire to annex Canada.

The war was fought in three theatres. At sea, warships and privateers of both sides attacked each other's merchant ships; the British blockaded the Atlantic coast of the U.S. and mounted large-scale raids in the later stages of the war. Both land and naval battles were fought on the American–Canadian frontier, which ran along the Great Lakes and the Saint Lawrence River. The American South and Gulf Coast also saw major land battles in which the American forces defeated Britain's Indian allies and repulsed the main British invasion force at New Orleans. Both sides invaded each other's territory, but these invasions were unsuccessful or temporary. At the end of the war, both sides occupied parts of the other's land, but these areas were restored by the Treaty of Ghent.