The Battle of Puebla took place on 5 May 1862 near the city of Puebla during the French intervention in Mexico. The battle ended in a victory for the Mexican Army against the occupying French forces. The victory is celebrated today during the festivities of Cinco de Mayo, the 5th of May.
The 1857-60 civil war in Mexico had disorganised the country's finances and the new President, Benito Juárez, was forced to suspend payments of foreign debts in 1861. In late 1861 Napoleon III, Emperor of the French, under the Treaty of London (1861) sent a joint expeditionary force to Mexico, alongside Spanish and English forces, to protect their interests and collect the debts owed by the previous Mexican government. The allied troops occupied the port city of Veracruz on December 8, 1861 and advanced to Orizaba. Napoleon III wanted to seize the opportunity presented by the U.S. involvement in the Civil War to set up a puppet Mexican regime. Napoleon's intrigues led to the withdrawal of the Spanish and British troops in April 1862. At the same time French reinforcements arrived.
The Battle of Puebla, May 5, 1862, was a single, important victory for the Mexican people over the occupying French Army. The French Army at the time was led by General Charles de Lorencez.
The battle came about by a misunderstanding of the French forces’ agreement to withdraw to the coast. To add to the mounting concerns, it was discovered that political negotiations for the withdrawal had broken down. A vehement complaint was lodged by the Mexicans to General Lorencez who took the effrontery as a plan to assail his forces. The 33 year old Mexican Commander General, Ignacio Zaragoza Seguín, fell back to Alcuzingo Pass, where he and his army were badly beaten in a skirmish with Lorencez's forces on April 28. Zaragoza retreated to Puebla, which was heavily fortified. To its north lie the forts Loreto and Guadalupe on opposite hilltops.
On May 5, against all advice, Lorencez decided to attack Puebla from the north. However, he started his attack a little too late in the day, using his artillery just before noon and by noon advancing his infantry. By the third attack the French required the full engagement of all their reserves. The French artillery had run out of ammunition, so the third infantry attack went unsupported. The Mexican forces and the Republican Garrison both put up a stout defense and even took to the field to defend the positions between the hilltop forts. As the French retreated from their final assault, Zaragoza had his cavalry attack them from the right and left while troops concealed along the road pivoted out to flank them badly. By 3 p.m. the daily rains had started, making a slippery quagmire of the battlefield. Lorencez withdrew to distant positions, counting 462 of his men killed against only 83 of the Mexicans.
On September 16, 1862, President Juárez declared that the anniversary of the Battle of Puebla would be a national holiday, regarded as "Battle of Puebla Day" or "Battle of Cinco de Mayo". Although today it is recognized in some countries as a day of Mexican heritage celebration, it is not a federal holiday in Mexico. A common misconception in the United States is that Cinco de Mayo is Mexico's Independence Day, the most important national patriotic holiday in Mexico. Grito de Dolores (Mexico's Independence Day) falls on September 16.