Thirteen colonies formed the original United States when independence was declared in 1776.
The colonies stretched along the Atlantic coast of British North America, from New Hampshire in the north to Georgia in the south. They were separately administered but shared political and legal traditions, and their delegates cooperated through the Continental Congress during the crisis with Britain.
The traditional groupings were the New England colonies, the Middle Colonies, and the Southern colonies. The thirteen were New Hampshire, Massachusetts, Rhode Island, Connecticut, New York, New Jersey, Pennsylvania, Delaware, Maryland, Virginia, North Carolina, South Carolina, and Georgia.
The number thirteen refers to the colonies that declared independence, not the number of states in the United States today. Vermont joined the Union later, while Kentucky and Tennessee were also admitted after the original founding era. The thirteen-star pattern on early American flags commemorated this founding group.