The real story of Cinco de Mayo weaves together two concurrent wars—the French intervention in Mexico (also known as The Maximillian Affair) and the American Civil War. On May 5, 1862, defending Mexican forces under Ignacio Zaragoza defeated Napoleon III's French army at Puebla, one of the most important Spanish colonial cities in Mexico. At the time, the French army was considered to be the most powerful fighting force in the world, and the unlikely Mexican victory resulted in a decree by then-Mexican President Benito Juárez that a celebration of the battle be held each year on May 5th. Cinco de Mayo was born, but it was about to be kidnapped.
As the French were making war with Mexico, the American Confederacy was courting Napoleon's help in its conflict with the United States. At the time of the Battle of Puebla, the Confederacy had strung together impressive victories over the Union forces. According to some historians, the French, who made war with Mexico on the pretext of collecting debt, planned to use Mexico as a "base" from which they could help the Confederacy defeat the North, and the Mexican victory at Puebla made the French pause long enough for the Union army to grow stronger and gain momentum. Had the French won at Puebla, some contend, the outcome of the American Civil War could have been much different, as the French and Confederates together could have taken control of the continent from the Mason Dixon line to Guatemela, installing an oligarchical, slave-holding government
