Cinco De Mayo Lessons, Worksheets and Activities Cinco de Mayo (Spanish for "Fifth of May") is a celebration held on May 5. The date is observed to commemorate the Mexican Army's unlikely victory over French forces at the Battle of Puebla on May 5, 1862, under the leadership of General Ignacio Zaragoza. In the United States, Cinco de Mayo has taken on a significance beyond that in Mexico. In ...