Which Congress adopted the Declaration of Independence in 1776?

The Second Continental Congress adopted the Declaration of Independence in 1776.

The Second Continental Congress met in Philadelphia beginning in May 1775, after the fighting at Lexington and Concord had begun the American Revolutionary War. It served as the revolutionary government of the Thirteen Colonies, directing the war effort, seeking foreign support, and acting on the growing demand for independence.

On July 2, 1776, Congress passed the Lee Resolution, declaring that the United Colonies should be free and independent states. Congress then debated and revised Thomas Jefferson's draft explanation of that decision. It adopted the Declaration on July 4, 1776, in the Pennsylvania State House, now Independence Hall.

The First Continental Congress had met in 1774 and coordinated colonial resistance, but it did not declare independence. “United States Congress” is the name of the later federal legislature created under the Constitution, while the Confederation Congress operated after the Articles of Confederation. The Declaration therefore belongs specifically to the Second Continental Congress, whose delegates represented the thirteen colonies.