Which document officially declared the separation of the colonies from Great Britain?

The Declaration of Independence is the document that officially proclaimed the separation of the American colonies from British rule. Adopted on July 4, 1776, it outlined the philosophical and political reasons for the colonies' decision to break away. The Declaration articulated key principles of government, including the rights of individuals to life, liberty, and the pursuit of happiness, and asserted that governments are instituted to secure these rights, deriving their just powers from the consent of the governed.

The significance of the Declaration lies in its clear statement of independence and its role in rallying support for the revolution both domestically and internationally. The other documents listed, such as the Articles of Confederation, primarily deal with governance after independence; the Emancipation Proclamation focuses on the abolition of slavery; and the Constitution sets the framework for the U.S. government but was created after independence was already declared.