Admission to the Union

The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 states and a federal capital district, Washington, D.C. The 48 contiguous states border Canada to the north and Mexico to the south, with the semi-exclave of Alaska in the northwest and the archipelago of Hawaii in the Pacific Ocean. The United States also asserts sovereignty over five major island territories and various uninhabited islands in Oceania and the Caribbean. It is a megadiverse country, with the world's third-largest land area and third-largest population, exceeding 340 million.

Paleo-Indians first migrated from North Asia to North America over 12,000 years ago, and formed various civilizations. Spanish colonization established Spanish Florida in 1513, the first European colony in what is now the continental United States. British colonization followed with the 1607 settlement of Virginia, the first of the Thirteen Colonies. Enslavement of Africans was practiced in all colonies by 1770 and supplied most of the labor for the Southern Colonies' plantation economy. Clashes with the British Crown over taxation and lack of parliamentary representation sparked the American Revolution, leading to the Declaration of Independence on July 4, 1776. Victory in the 1775–1783 Revolutionary War brought international recognition of U.S. sovereignty and fueled westward expansion, dispossessing native inhabitants. As more states were admitted, a North–South division over slavery led the Confederate States of America to attempt secession and fight the Union in the 1861–1865 American Civil War. With the United States' victory and reunification, slavery was abolished nationally. By 1900, the country had established itself as a great power, a status solidified after its involvement in World War I. Following Japan's attack on Pearl Harbor in 1941, the U.S. entered World War II. Its aftermath left the U.S. and the Soviet Union as rival superpowers, competing for ideological dominance and international influence during the Cold War. The Soviet Union's collapse in 1991 ended the Cold War, leaving the U.S. as the world's sole superpower.

Territories of the United States are subnational geographical and political areas governed as administrative divisions and dependent territories under the sovereignty of the United States. Despite all being subject to the constitutional and territorial jurisdiction of the U.S. federal government, territories differ from states and Indian reservations in that they are not inherently sovereign. While states have dual sovereignty and Native American tribes have tribal sovereignty in relation to the federal government, the self-governing powers of territories ultimately derive from the U.S. Congress, as per the Territorial Clause in Article IV of the U.S. Constitution. Territories are classified as "organized" or "unorganized" depending on whether they operate under an organic act, and "incorporated" or "unincorporated" depending on whether the U.S. Constitution applies fully or partially to them. As areas belonging to, but not integral parts of, the U.S., territories are their own distinct nations centered around a collective identity based on their land, history, ethnicity, culture, and language.

All territories of the U.S. are insular areas. The U.S. has sovereignty over three archipelagos or islands in the Caribbean Sea and eleven in the Pacific Ocean. Five territories (American Samoa, Guam, the Northern Mariana Islands, Puerto Rico, and the United States Virgin Islands) are permanently inhabited, unincorporated territories; the other nine are small islands, atolls, and reefs with no native (or permanent) population. Of the 14, only one is classified as an incorporated territory (Palmyra Atoll). Two additional territories (Bajo Nuevo Bank and Serranilla Bank) are claimed by the U.S. but administered by Colombia. Historically, territories were created to administer newly acquired land, and most eventually attained statehood. The most recent territory to become a U.S. state was Hawaii on August 21, 1959.

Vermont (/vərˈmɒnt/ ) is a landlocked state in the New England region of the Northeastern United States. It borders Massachusetts to the south, New Hampshire to the east, New York to the west, and the Canadian province of Quebec to the north. According to the most recent U.S. census estimates, the state has an estimated population of 648,493, making it the second-least populated of all U.S. states. It is the nation's sixth-smallest state by total area. The state's capital of Montpelier is the least populous U.S. state capital. No other U.S. state has a most populous city with fewer residents than Burlington.

Native Americans have inhabited the area for about 12,000 years. The competitive tribes of the Algonquian-speaking Abenaki and Iroquoian-speaking Mohawk were active in the area at the time of European encounter. During the 17th century, French colonists claimed the territory as part of New France. Conflict arose when the Kingdom of Great Britain began to settle colonies to the south along the Atlantic coast; France was defeated in 1763 in the Seven Years' War, ceding its territory east of the Mississippi River to Britain. Thereafter, the nearby British Thirteen Colonies disputed the extent of the area called the New Hampshire Grants to the west of the Connecticut River, encompassing present-day Vermont. The provincial government of New York sold land grants to settlers in the region, which conflicted with earlier grants from the government of New Hampshire. The Green Mountain Boys militia protected the interests of the established New Hampshire land grant settlers. Ultimately, a group of settlers with New Hampshire land grant titles established the Vermont Republic in 1777 as an independent state during the American Revolutionary War. The Vermont Republic abolished slavery before any other U.S. state. It was admitted to the Union in 1791 as the 14th state.

The United States of America is a federal republic consisting of 50 states, a federal district (Washington, D.C., the capital city of the United States), five major territories, and minor islands. Both the states and the United States as a whole are each sovereign jurisdictions. The Tenth Amendment to the United States Constitution allows states to exercise all powers of government not delegated to the federal government. Each state has its own constitution and government. All states and their residents are represented in the federal Congress, a bicameral legislature consisting of the Senate and the House of Representatives. Each state elects two senators, while representatives are distributed among the states in proportion to the most recent constitutionally mandated decennial census.

Each state is entitled to select a number of electors to vote in the Electoral College, the body that elects the president of the United States, equal to the total of representatives and senators in Congress from that state. The federal district does not have representatives in the Senate, but has a non-voting delegate in the House, and it is entitled to electors in the Electoral College. Congress can admit more states, but it cannot create a new state from territory of an existing state or merge two or more states into one without the consent of all states involved. Each new state is admitted on an equal footing with the existing states.

The contiguous United States, also known as the U.S. mainland, officially referred to as the conterminous United States, consists of the 48 adjoining U.S. states and the District of Columbia of the United States in central North America. The term excludes the only two non-contiguous states and the last two to be admitted to the Union, which are Alaska and Hawaii, and all other offshore insular areas, such as the U.S. territories of American Samoa, Guam, the Northern Mariana Islands, Puerto Rico, and the U.S. Virgin Islands. The colloquial term Lower 48 is also used, especially in relation to Alaska. The term The Mainland is used in Hawaii. The related but distinct term continental United States includes Alaska, which is also in North America, but separated from the 48 states by British Columbia in Canada, but excludes Hawaii and all the insular areas in the Caribbean and the Pacific.

The greatest distance on a great-circle route entirely within the contiguous U.S. is 2,802 miles (4,509 km), coast-to-coast between Florida and Washington state; the greatest north–south line is 1,650 miles (2,660 km). The contiguous United States occupies an area of 3,119,884.69 square miles (8,080,464.3 km). Of this area, 2,959,064.44 square miles (7,663,941.7 km) is actual land, composing 83.65 percent of the country's total land area, and is comparable in size to the area of Australia. Officially, 160,820.25 square miles (416,522.5 km) of the contiguous United States is water area, composing 62.66 percent of the nation's total water area.

Maine (/meɪn/ MAYN) is a state in the New England region of the United States, and the northeasternmost state in the contiguous United States. It borders New Hampshire to the west, the Gulf of Maine to the southeast, and the Canadian provinces of New Brunswick and Quebec to the northeast and northwest, and shares a maritime border with Nova Scotia. It is the only state to border only one other state, which is New Hampshire. Maine is the largest state in New England by total area, almost as large as the combined area of the remaining five states. Of the 50 U.S. states, it is the 12th-smallest by area, the 9th-least populous, the 13th-least densely populated, and the most rural. As of 2024, Maine's population stood at a Census-estimated 1,405,012, the state's highest-ever population estimate. Maine's capital is Augusta, while its most populous city is Portland.

The territory of Maine has been inhabited by Indigenous populations for about 12,000 years, after the glaciers retreated during the last ice age. At the time of European arrival, several Algonquian-speaking nations governed the area and these nations are now known as the Wabanaki Confederacy. The first European settlement in the area was by the French in 1604 on Saint Croix Island, founded 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 Irish and English settlements were established along the coast of Maine in the 1620s, although the rugged climate and conflict with the local Indigenous people caused many to fail. 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. During the War of 1812, the largely undefended eastern region of Maine was occupied by British forces with the goal of annexing it to Canada via the Colony of New Ireland, but returned to the United States following failed British offensives on the northern border, mid-Atlantic and south which produced a peace treaty that restored the pre-war boundaries. 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, Maine was admitted to the Union as the 23rd state.