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The biggest misconception about Cinco de Mayo is that it commemorates of México's Independence Day. That holiday is, in fact, celebrated on September 16. On that date back in 1810, Father Miguel Hidalgo issued a proclamation known as "El Grito de Dolores" that united the many different rebellions going on against Spain into one cohesive struggle. México achieved its independence from Spanish rule in 1821. Cinco de Mayo is actually a commemoration of a victory by Mexican troops in La Batalla de Puebla more that fifty years later, on May 5, 1862.
What is the significance behind Cinco de Mayo?