 Early festivities included public readings of the Declaration of Independence, and the tradition of setting off fireworks started in Philadelphia, July 4th, 1777, complete with a 13-gun ship's cannon salute to the colonies. Patriotic celebrations grew after the War of 1812, and in 1870, Congress made July 4th a federal holiday. Happy birthday, America. Tanya J. Powers, Fox News. It's time for a Tech Mobility Minute.