History of AMERICA: The story of how the United States was formed from various territories

The first people arrived in the Americas approximately 15,000 BC, marking the beginning of the history of the areas that would later become the United States. Many different indigenous civilizations emerged, and in the 16th century, many of them underwent transitions away from highly populated ways of life and toward reformed polities. Although European colonization of the Americas dates back to the 1500s, the vast majority of the colonies that would eventually form the United States were established around 1600. The thirteen British colonies east of the Appalachians on the Atlantic coast had a combined population of 2.5 million by the 1760s. Slave labor was the backbone of the agricultural economy in the Southern Colonies, which relied on people brought over from Africa for that purpose. British authorities, emboldened by their victory over France, enacted a number of additional levies, most notably the Stamp Act of 1765, without consulting the colonies as required by their constitution. Parliament issued harsh measures intended to eliminate self-government in response to resistance to these taxes, most notably the Boston Tea Party in 1773. In 1775, violent strife broke out in Massachusetts.