Cinco de Mayo festivities are taking place across the U.S. with music, tacos, tequila and colorful displays of Mexican culture — even if they're not always the most authentic.

The holiday actually commemorates the Mexican army’s victory over French forces at the Battle of Puebla on May 5, 1862.

Here's why Cinco de Mayo is a significant date in Mexican history, and it has nothing to do with margaritas or Mexican ...