You’ve probably heard of Cinco de Mayo before, and you may even have celebrated it before. But if you’re like most people, you may not know about the history of the holiday, what it means, and why it’s so significant.

Cinco de Mayo is the fifth of May, and while many people assume that the holiday is about Mexican independence, the celebration is actually for events that happened more than 50 years after Mexico gained this independence. While the holiday is actually relatively minor in Mexico, in the United States it is a chance to celebrate Mexican heritage and culture, especially in areas and states that have large populations of Mexican-Americans.

These traditions include mariachi music, parades, and street festivals throughout Mexico and the United States, and it’s a chance to dress up in a costume (like the ones from Disguises), eat some Mexican food, and have a few margaritas while learning about the holiday.

In 1861, Beneto Juarez was president of Mexico, and as he became president the country was unfortunately completely broke. This caused him to announce that Mexico would be defaulting on their debts to many European governments, so Spain, Britain and France sent their navel forces to the town of Veracruz in order to demand that they be reimbursed. While Spain and Britain spent some time negotiating with the Mexican government and eventually withdrew their troops, France was under the rule of Napoleon III and he decided to take advantage of this opportunity and make Mexico a dependent territory of France.

Near the end of 1861, the French stormed Veracruz, landing on the Mexican shores and sending the Mexican government and President Juarez into retreat. The French were certain of their success, and 6,000 troops were sent to attack a small town called Puebla de Los Angeles. President Juarez managed to find a rag-tag army of just 2,000 men (many of them of mixed ancestry or indigenous) and sent them to defend the town.

This group was led by General Ignacio Zaragoza and the group were both poorly supplied and vastly outnumbered, although they prepared for the assault and fortified the town as best they could.

On the 5th of May, 1862, the French moved into position, backed by heavy artillery and very well-provisioned, and assaulted the town from the north. The battle lasted all day, and the French ended up retreating after losing almost 500 soldiers, while fewer than 100 Mexicans died during the battle.

While the battle wasn’t a major win strategically when it came to the Mexican’s war with the French, the success that the Mexicans experienced at Puebla was a hugely symbolic victory and managed to bolster the resistance movement, and six years later (with the help of the United States), France ended up withdrawing from the country.

The holiday is now a celebration of Mexican culture and also a celebration of the Mexican victory over the French.