The major historical document that announced the thirteen colonies' separation from British rule was the Declaration of Independence, adopted on July 4, 1776. Primarily drafted by Thomas Jefferson, this document articulated the colonies' grievances against King George III and outlined the Enlightenment principles of natural rights and government by consent. The declaration marked a critical turning point, as it formally severed political ties with Britain, paving the way for the American Revolution. It set forth the foundational notion of equality and the pursuit of happiness, influencing democratic movements worldwide.