- The Declaration of Independence, formally titled The unanimous Declaration of the thirteen united States of America (in the engrossed version but not the original printing), is the founding document of the United States. On July 4, 1776, it was adopted unanimously by the 56 delegates to the Second Continental Congress, who had convened at the Pennsylvania State House, later renamed Independence Hall, in the colonial era capital of Philadelphia. The declaration explains to the world why the Thirteen Colonies regarded themselves as independent sovereign states no longer subject to British colonial rule.