The tensions that caused the War of 1812 arose from the French revolutionary (1792–99) and Napoleonic Wars (1799–1815). During this nearly constant conflict between France and Britain, American interests were injured by each of the two countries’ endeavours to block the United States from trading with the other.

Causes of the war included British attempts to restrict U.S. trade, the Royal Navy’s impressment of American seamen and America’s desire to expand its territory.

The War of 1812 was fought between the United States and Great Britain over trade restrictions, the impressment of American sailors, and British support for Native American Indian attacks against Americans living on the Western Frontier.

War of 1812, U.S.-British conflict arising from U.S. grievances over oppressive British maritime practices in the Napoleonic Wars. To enforce its blockade of French ports, the British boarded U.S. and other neutral ships to check cargo they suspected was being sent to France and to impress seamen alleged to be British navy deserters.

Resentment for Britain’s interference with American international trade, combined with American expansionist visions, led Congress to declare war on Great Britain on June 18, 1812.