The Battle of Plattsburgh, also known as the Battle of Lake Champlain, ended the final British invasion of the northern states of the United States during the War of 1812. Two British forces, an army under Lieutenant General Sir George Prévost and a naval squadron under Captain George Downie converged on the lakeside town of Plattsburgh, New York. Plattsburgh was defended by New York and Vermont militia and detachments of regular troops of the United States Army, all under the command of Brigadier General Alexander Macomb, and ships commanded by Master Commandant Thomas Macdonough.

The War of 1812 was fought by the United States and its allies against the United Kingdom and its allies in North America. It began when the United States declared war on Britain on 18 June 1812. Although peace terms were agreed upon in the December 1814 Treaty of Ghent, the war did not officially end until the peace treaty was ratified by the United States Congress on 17 February 1815.