It’s kind of the equivalent of Patriot’s Day in the United States. It has nothing to do with Mexican independence, contrary to what a lot of Americans may think.
It actually commemorates the Battle of Puebla in 1865 when a small band of Mexican fighters defeated French invaders. In fact, it’s even considered a minor holiday in the region where it is observed, Puebla. Cinco de Mayo is not a major holiday in Mexico.
