The historical event celebrated on the Fourth of July in the United States is the Declaration of Independence, which was adopted on July 4, 1776. This document, primarily authored by Thomas Jefferson, announced the thirteen American colonies' separation from British rule. The Declaration signified the colonies' desire for self-governance and fundamental rights, declaring that all individuals possess unalienable rights, including life, liberty, and the pursuit of happiness. The day is observed with various celebrations, including fireworks, parades, and barbecues, symbolizing American patriotism and freedom. Over time, the Fourth of July has become a cornerstone of American identity and culture.