Each year on the 5th of May, Cinco de Mayo celebrations are held in cities throughout the United States. And yet, few people outside of Mexico are fully aware of the holiday’s true significance. It is a story that began on a sweltering May morning in 1862, in the city of Puebla, Mexico, when Mexican forces were besieged by the invading French Army. However, instead of a noble defeat, the Mexican people engineered a stunning and unexpected victory. With the help of esteemed scholars and a host of rare archival material, this captivating program from HISTORY takes an in-depth look into the heart of the 19th-century battle which changed the course of New World history forever. Filmed in both Mexico and the U.S., this is the riveting story of the day an ill-equipped Mexican army, together with the Zacapoaxtla Indians and everyday Mexican citizens, bravely defeated occupying French forces to reclaim their land and secure their independence.