Paleo-Indians migrated from Siberia to the North American mainland at least 12,000 years ago.[22] 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, and 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.[23] 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,[24] displacing Native American tribes, and gradually admitting new states until it spanned the continent by 1848.[24]

During the second half of the 19th century, the Civil War led to the abolition of slavery.[25][26] By the end of the century, the United States had extended into the Pacific Ocean,[27] and its economy, driven in large part by the Industrial Revolution, began to soar.[28] The Spanish