The historical event commemorated on the Fourth of July in the United States is the signing of the Declaration of Independence in 1776. This declaration marked the thirteen American colonies' formal separation from British rule, asserting their right to self-governance and freedom. The day is celebrated with various festivities, including fireworks, parades, barbecues, and patriotic displays. It symbolizes the values of liberty, democracy, and national identity. Independence Day serves as a reminder of the sacrifices made for freedom and the ongoing pursuit of these ideals in American society.