It's commonly thought that Cinco de Mayo ("The fifth of May" in Spanish) is Mexico's Independence Day, but the day actually commemorates the Battle of Puebla. On May 5, 1861, Mexican forces led by General Ignacio Zaragoza conquered the French occupation forces near the city of Puebla. It's this victory that's celebrated every May 5 throughout Mexico and the U.S, while Mexico's Independence Day is celebrated September 16.