Maine () is a U.S. state in the New England region of the northeastern United States. Maine is the 11th least extensive and the 9th least populous of the U.S. states. It is bordered by New Hampshire to the west, the Atlantic Ocean to the southeast, and the Canadian provinces of New Brunswick and Quebec to the northeast and northwest respectively. Maine is the easternmost state in the contiguous United States, and the northernmost east of the Great Lakes. It is known for its jagged, rocky coastline; low, rolling mountains; heavily forested interior; and picturesque waterways, as well as its seafood cuisine, especially clams and lobster. There is a humid continental climate throughout the state, even in coastal areas such as its most populous city of Portland. The capital is Augusta.
For thousands of years, indigenous peoples were the only inhabitants of the territory that is now Maine. At the time of European arrival in what is now Maine, several Algonquian-speaking peoples inhabited the area. The first European settlement in the area was by the French in 1604 on Saint Croix Island, by Pierre Dugua, Sieur de Mons. The first English settlement was the short-lived Popham Colony, established by the Plymouth Company in 1607. A number of English settlements were established along the coast of Maine in the 1620s, although the rugged climate, deprivations, and conflict with the local peoples caused many to fail over the years.
As Maine entered the 18th century, only a half dozen European settlements had survived. Loyalist and Patriot forces contended for Maine's territory during the American Revolution and the War of 1812. At the close of the War of 1812, it was occupied by British forces, but the territory of Maine was returned to the United States as part of a peace treaty that was to include dedicated land on the Michigan peninsula for Native American peoples. Maine was part of the Commonwealth of Massachusetts until 1820, when it voted to secede from Massachusetts to become a separate state. On March 15, 1820, under the Missouri Compromise, it was admitted to the Union as the 23rd state.