The War of 1812 was a military conflict, lasting for two-and-a-half years, between the United States of America and the United Kingdom of Great Britain and Ireland, its North American colonies and its American Indian allies. Seen by the United States and Canada as a war in its own right, it is frequently seen in Europe as a theatre of the Napoleonic Wars, as it was caused by issues related to that war (especially the Continental System). The war resolved many issues which remained from the American Revolutionary War but involved no boundary changes. The United States declared war on June 18, 1812 for several reasons, including trade restrictions brought about by the British war with France, the impressment of American merchant sailors into the Royal Navy, British support of Indian tribes against American expansion, outrage over insults to national honor after humiliations on the high seas, and possible American interest in annexing British territory in modern-day Canada. The war was fought in three principal theatres. Firstly, at sea, warships and privateers of each side attacked the other’s merchant ships, while the British blockaded the Atlantic coast of the United States and mounted large raids in the later stages of the war. Secondly, land and naval battles were fought on the American–Canadian frontier, which ran along the Great Lakes, the Saint Lawrence River and the northern end of Lake Champlain. Thirdly, the American South and Gulf Coast also saw big land battles, in which the American forces defeated Britain’s Indian allies and a British invasion force at New Orleans. At the end of the war both sides signed the Treaty of Ghent and both parties returned occupied land to its pre-war owner and resumed friendly trade relations. With the majority of its land and naval forces tied down in Europe fighting the Napoleonic Wars, the British used a defensive strategy in the Provinces of Upper and Lower Canada, repelling initial American invasions. This demonstrated that the conquest of the Canadas would prove more difficult than anticipated. However, the Americans gained control of Lake Erie in 1813, seized parts of western Ontario, and ended the prospect of an Indian confederacy and an independent Indian state in the Midwest under British sponsorship. In April 1814, with the defeat of Napoleon, the British adopted a more aggressive strategy, sending larger invasion armies. In September 1814, the British invaded and occupied eastern Maine. In the south-west, General Andrew Jackson destroyed the military strength of the Creek nation at the Battle of Horseshoe Bend. The British victory at the Battle of Bladensburg in August 1814 allowed them to capture and burn Washington, D.C, but they were repulsed in an attempt to take Baltimore. American victories in September 1814 at the Battle of Plattsburgh repulsed the British invasions of New York, which along with pressure from merchants on the British government prompted British diplomats to drop their demands at Ghent for an independent native buffer state and territorial claims that London previously sought. Both sides agreed to a peace that restored the situation before the war began. However, it took six weeks for ships to cross the Atlantic so news of the peace treaty did not arrive before the British suffered a major defeat at New Orleans in January 1815. In the United States, late victories over invading British armies at the battles of Plattsburg, Baltimore (inspiring their national anthem, “The Star-Spangled Banner”) and New Orleans produced a sense of euphoria over a “second war of independence” against Britain. The Federalist Party had strongly opposed the war effort and prevented New England from providing much in the way of soldiers and troops; it now virtually collapsed. The war ended on a high note for Americans, bringing an “Era of Good Feelings” in which partisan animosity nearly vanished in the face of strengthened U.S. nationalism. Spain played a small role, but was not an official belligerent; some Spanish forces fought alongside the British during the Occupation of Pensacola. The U.S. took permanent ownership of Spain’s Mobile District. In Upper and Lower Canada, British and Provincial militia victories over invading American armies became iconic and promoted the development of a distinct Canadian identity, which included strong loyalty to Britain. Today, particularly in Ontario, memory of the war retains its significance, because the defeat of the invasions ensured that the Canadas would remain part of the British Empire, rather than be annexed by the United States. In Canada, numerous ceremonies took place in 2012 to commemorate the war, offer historical lessons and celebrate 200 years of peace across the border. The war is scarcely remembered in Britain, where attention focuses on the closer threat of Napoleon.