The siege of Fort of Mackinac was one of the first engagements of the War of 1812. A British and Native American force captured the island soon after the outbreak of war between Britain and the United States. Encouraged by the easy British victory, more Native Americans rallied to their support. Their cooperation was an important factor in several British victories during the remainder of the war.

Mackinac Island is an island and resort area, covering 4.35 square miles (11.3 km2) in land area, in the U.S. state of Michigan. The name of the island in Odawa is Michilimackinac and "Mitchimakinak" in Ojibwemowin, meaning "Great Turtle". It is located in Lake Huron, at the eastern end of the Straits of Mackinac, between the state's Upper and Lower Peninsulas. The island was long home to an Odawa settlement and previous indigenous cultures before European colonization began in the 17th century. It was a strategic center of the fur trade around the Great Lakes. Based on a former trading post, Fort Mackinac was constructed on the island by the British during the American Revolutionary War. It was the site of two battles during the War of 1812 before the northern border was settled and the US gained this island in its territory.