In 1812, a significant event was the outbreak of the War of 1812 between the United States and Great Britain. The war formally began when the United States declared war on Britain on June 18, 1812, due to several grievances including British restrictions on American trade through the Orders-in-Council and the impressment of American sailors into the British Royal Navy

. Key developments in 1812 included:

• The United States launched invasions into British-held Canada starting July 12, 1812, with an army crossing into Upper Canada (now Ontario). However, these invasions largely failed due to lack of supplies and strong British and Indigenous resistance

• British forces, led by Major General Isaac Brock, captured Detroit in August 1812 after the American commander William Hull surrendered. This was a major early British victory

• American attempts to invade Canada continued but were repelled, including a failed attack at Queenston Heights in October 1812, where British General Brock was killed

• The war was marked by frontier battles and conflicts involving Native American allies on both sides

The War of 1812 was rooted in maritime disputes, trade restrictions, and territorial ambitions in North America. It was the first formal war declared by the United States and had mixed military outcomes in its initial year, setting the stage for continued conflict until the war ended in 1815 with the Treaty of Ghent

. Thus, 1812 is largely remembered for the beginning of the War of 1812, a conflict that shaped early U.S. history and its relations with Britain and Canada.