The United States of America known as the United States or America, is a country composed of 50 states, a federal district, five major self-governing territories, various possessions. At 3.8 million square miles, the United States is the world's third or fourth largest country by total area and is smaller than the entire continent of Europe's 3.9 million square miles. With a population of over 327 million people, the U. S. is the third most populous country. The capital is Washington, D. C. and the largest city by population is New York City. Forty-eight states and the capital's federal district are contiguous in North America between Canada and Mexico; the State of Alaska is in the northwest corner of North America, bordered by Canada to the east and across the Bering Strait from Russia to the west. The State of Hawaii is an archipelago in the mid-Pacific Ocean; the U. S. territories are scattered about the Pacific Ocean and the Caribbean Sea, stretching across nine official time zones. The diverse geography and wildlife of the United States make it one of the world's 17 megadiverse countries.
Paleo-Indians migrated from Siberia to the North American mainland at least 12,000 years ago. European colonization began in the 16th century; the United States emerged from the thirteen British colonies established along the East Coast. Numerous disputes between Great Britain and the colonies following the French and Indian War led to the American Revolution, which began in 1775, the subsequent Declaration of Independence in 1776; the war ended in 1783 with the United States becoming the first country to gain independence from a European power. The current constitution was adopted in 1788, with the first ten amendments, collectively named the Bill of Rights, being ratified in 1791 to guarantee many fundamental civil liberties; the United States embarked on a vigorous expansion across North America throughout the 19th century, acquiring new territories, displacing Native American tribes, admitting new states until it spanned the continent by 1848. During the second half of the 19th century, the Civil War led to the abolition of slavery.
By the end of the century, the United States had extended into the Pacific Ocean, its economy, driven in large part by the Industrial Revolution, began to soar. The Spanish–American War and World War I confirmed the country's status as a global military power; the United States emerged from World War II as a global superpower, the first country to develop nuclear weapons, the only country to use them in warfare, a permanent member of the United Nations Security Council. Sweeping civil rights legislation, notably the Civil Rights Act of 1964, the Voting Rights Act of 1965 and the Fair Housing Act of 1968, outlawed discrimination based on race or color. During the Cold War, the United States and the Soviet Union competed in the Space Race, culminating with the 1969 U. S. Moon landing; the end of the Cold War and the collapse of the Soviet Union in 1991 left the United States as the world's sole superpower. The United States is the world's oldest surviving federation, it is a representative democracy.
The United States is a founding member of the United Nations, World Bank, International Monetary Fund, Organization of American States, other international organizations. The United States is a developed country, with the world's largest economy by nominal GDP and second-largest economy by PPP, accounting for a quarter of global GDP; the U. S. economy is post-industrial, characterized by the dominance of services and knowledge-based activities, although the manufacturing sector remains the second-largest in the world. The United States is the world's largest importer and the second largest exporter of goods, by value. Although its population is only 4.3% of the world total, the U. S. holds 31% of the total wealth in the world, the largest share of global wealth concentrated in a single country. Despite wide income and wealth disparities, the United States continues to rank high in measures of socioeconomic performance, including average wage, human development, per capita GDP, worker productivity.
The United States is the foremost military power in the world, making up a third of global military spending, is a leading political and scientific force internationally. In 1507, the German cartographer Martin Waldseemüller produced a world map on which he named the lands of the Western Hemisphere America in honor of the Italian explorer and cartographer Amerigo Vespucci; the first documentary evidence of the phrase "United States of America" is from a letter dated January 2, 1776, written by Stephen Moylan, Esq. to George Washington's aide-de-camp and Muster-Master General of the Continental Army, Lt. Col. Joseph Reed. Moylan expressed his wish to go "with full and ample powers from the United States of America to Spain" to seek assistance in the revolutionary war effort; the first known publication of the phrase "United States of America" was in an anonymous essay in The Virginia Gazette newspaper in Williamsburg, Virginia, on April 6, 1776. The second draft of the Articles of Confederation, prepared by John Dickinson and completed by June 17, 1776, at the latest, declared "The name of this Confederation shall be the'United States of America'".
The final version of the Articles sent to the states for ratification in late 1777 contains the sentence "The Stile of this Confederacy shall be'The United States of America'". In June 1776, Thomas Jefferson wrote the phrase "UNITED STATES OF AMERICA" in all capitalized letters in the headline of his "original Rough draught" of the Declaration of Independence; this draft of the document did not surface unti
Greenland is an autonomous constituent country of the Kingdom of Denmark between the Arctic and Atlantic oceans, east of the Canadian Arctic Archipelago. Though physiographically a part of the continent of North America, Greenland has been politically and culturally associated with Europe for more than a millennium; the majority of its residents are Inuit, whose ancestors began migrating from the Canadian mainland in the 13th century settling across the island. Greenland is the world's largest island. Three-quarters of Greenland is covered by the only permanent ice sheet outside Antarctica. With a population of about 56,480, it is the least densely populated territory in the world. About a third of the population live in the capital and largest city; the Arctic Umiaq Line ferry acts as a lifeline for western Greenland, connecting the various cities and settlements. Greenland has been inhabited at intervals over at least the last 4,500 years by Arctic peoples whose forebears migrated there from what is now Canada.
Norsemen settled the uninhabited southern part of Greenland beginning in the 10th century, having settled Iceland to escape persecution from the King of Norway and his central government. These Norsemen would set sail from Greenland and Iceland, with Leif Erikson becoming the first known European to reach North America nearly 500 years before Columbus reached the Caribbean islands. Inuit peoples arrived in the 13th century. Though under continuous influence of Norway and Norwegians, Greenland was not formally under the Norwegian crown until 1262; the Norse colonies disappeared in the late 15th century when Norway was hit by the Black Death and entered a severe decline. Soon after their demise, beginning in 1499, the Portuguese explored and claimed the island, naming it Terra do Lavrador. In the early 18th century, Danish explorers reached Greenland again. To strengthen trading and power, Denmark–Norway affirmed sovereignty over the island; because of Norway's weak status, it lost sovereignty over Greenland in 1814 when the union was dissolved.
Greenland became Danish in 1814, was integrated in the Danish state in 1953 under the Constitution of Denmark. In 1973, Greenland joined the European Economic Community with Denmark. However, in a referendum in 1982, a majority of the population voted for Greenland to withdraw from the EEC, effected in 1985. Greenland contains the world's largest and most northerly national park, Northeast Greenland National Park. Established in 1974, expanded to its present size in 1988, it protects 972,001 square kilometres of the interior and northeastern coast of Greenland and is bigger than all but twenty-nine countries in the world. Greenland is divided into five municipalities – Sermersooq, Qeqertalik and Avannaata. Greenland does not have an independent seat at the United Nations. In 1979, Denmark granted home rule to Greenland, in 2008, Greenlanders voted in favor of the Self-Government Act, which transferred more power from the Danish government to the local Greenlandic government. Under the new structure, in effect since 21 June 2009, Greenland can assume responsibility for policing, judicial system, company law and auditing.
It retains control of monetary policy, providing an initial annual subsidy of DKK 3.4 billion, planned to diminish over time. Greenland expects to grow its economy based on increased income from the extraction of natural resources; the capital, held the 2016 Arctic Winter Games. At 70%, Greenland has one of the highest shares of renewable energy in the world coming from hydropower; the early Norse settlers named the island as Greenland. In the Icelandic sagas, the Norwegian-born Icelander Erik the Red was said to be exiled from Iceland for manslaughter. Along with his extended family and his thralls, he set out in ships to explore an icy land known to lie to the northwest. After finding a habitable area and settling there, he named it Grœnland in the hope that the pleasant name would attract settlers; the Saga of Erik the Red states: "In the summer, Erik left to settle in the country he had found, which he called Greenland, as he said people would be attracted there if it had a favorable name."The name of the country in the indigenous Greenlandic language is Kalaallit Nunaat.
The Kalaallit are the indigenous Greenlandic Inuit people. In prehistoric times, Greenland was home to several successive Paleo-Eskimo cultures known today through archaeological finds; the earliest entry of the Paleo-Eskimo into Greenland is thought to have occurred about 2500 BC. From around 2500 BC to 800 BC, southern and western Greenland were inhabited by the Saqqaq culture. Most finds of Saqqaq-period archaeological remains have been around Disko Bay, including the site of Saqqaq, after which the culture is named. From 2400 BC to 1300 BC, the Independence I culture existed in northern Greenland, it was a part of the Arctic small tool tradition. Towns, including Deltaterrassern