The Thirteen Colonies, also known as the Thirteen British Colonies or Thirteen American Colonies, were a group of British colonies on the Atlantic coast of North America founded in the 17th and 18th centuries. They declared independence in 1776 and formed the United States of America. The Thirteen Colonies had very similar political, constitutional, and legal systems and were dominated by Protestant English-speakers. They were part of Britain's possessions in the New World, which also included colonies in Canada, the Caribbean, and the Floridas.
Between 1625 and 1775, the colonial population grew from roughly 2,000 to over 2.5 million, sometimes displacing American Indians. This population included people subject to a system of slavery, which was legal in all of the colonies prior to the American Revolutionary War. In the 18th century, the British government operated its colonies under a policy of mercantilism, in which the central government administered its possessions for the economic benefit of the mother country.
The Thirteen Colonies had a high degree of self-governance and active local elections, and they resisted London's demands for more control. The French and Indian War (1754–63) against France and its Indian allies led to growing tensions between Britain and the Thirteen Colonies. In the 1750s, the colonies began collaborating with one another instead of dealing directly with Britain. These inter-colonial activities cultivated a sense of shared American identity and led to calls for protection of the colonists' "Rights as Englishmen", especially the principle of "no taxation without representation". Grievances with the British government led to the American Revolution, in which the colonies collaborated in forming the Continental Congress. The colonists fought the American Revolutionary War (1775–83) with the aid of France and, to a significantly smaller degree, the Dutch Republic and Spain.
In London beginning in 1660, all colonies were governed through a state department known as the Southern Department, and a committee of the Privy Council called the Board of Trade and Plantations. In 1768, a specific state department was created for America, but it was disbanded in 1782 when the Home Office took responsibility.