Cinco de mayo has 2 different meanings across 2 categories:
the fifth of May which is observed in Mexico and Mexican-American communities in the United States to commemorate the Mexican victory over the French in the Battle of Puebla in 1862
A national celebration in Mexico, commemorating the victory of Mexican forces led by General Ignacio Zaragoza over the French expeditionary forces in the Battle of Puebla on May 5, 1862, also celebrated widely by immigrants living in the United States.