Paleo-Indians migrated to what is now the United States mainland from Asia around 12,000 years ago. They eventually adopted a maize-based agriculture from modern-day Mexico; this supported population growth and specialization in crafts. After European explorers and traders first made contact, largely in the 16th century, the local population greatly declined, mostly due to diseases such as smallpox and measles to which indigenous Americans had no natural immunities.
The first successful British colony, Jamestown, was founded in 1607; in time, a total of thirteen colonies were founded. There was large-scale immigration into the Colonies, and slowly they gained in power and self-reliance. To pay for the Seven Years War (1756-1763), which ensured the protection of the colonies from French incursions, the British government raised taxes. A rebellious spirit started to form, particularly in Boston, a city with a high proportion of Irish immigrants. English rule in Ireland was at times genuinely tyrannical, but that in the Thirteen Colonies was not. Despite their accusations of 'tyranny', American Colonists were not treated nearly as badly by their home country as those in French and Spanish colonies.
The rebellion gained ground, and the American War of Independence began in earnest in 1776, following the Declaration of Independence on 4 July. Thanks to substantial aid and military assistance from the French, Spanish and Dutch (and some spectacular blunders by British generals), the colonists won the war at the Battle of Yorktown in 1781. Britain officially recognised the independence of the United States on 3 September 1783. This was the first successful war of independence against a European colonial empire. The current US Constitution was adopted in 1787, with 10 amendments, collectively named the Bill of Rights, being ratified in 1791.
The USA's gross domestic product accounts for close to a quarter of the world's total, and its military budget is reckoned to be almost as much as the rest of the world's defence spending put together. The country is also a major source of entertainment, ranging from television, Hollywood films, jazz, blues, rock and rap.
Politics in the United States is dominated by two major party coalitions, the Democratic Party and the Republican Party. The Democratic Party evolved from the party of Thomas Jefferson in the late 1700s, while the Republican Party was formed by a coalition opposed to slavery in the 1850s.
Coordinates: 40.4230° N, 98.7372° W
Capital: Washington D.C
Capital Coordinates: 38°53'N 77°01'W
Other Main Cities: New York, Chicargo, Los Angeles, Houston, Phoenix, San Francisco, San Diago, Dallas
Official Language(s): English
Ethnic Group(s): white 79.96%, black 12.85%, Asian 4.43%, Amerindian and Alaska native 0.97%, native Hawaiian and other Pacific islander 0.18%, two or more races 1.61%
Currency: Dollar, $
GDP: $15.685 trillion
Time Zone: (UTC-5 to -10), Summer (DST) (UTC-4 to -10[e])
International Dialling Code: 1
Internet TLD: .us
Electricity Voltage: 120 Volts AC (60HZ)