Cinco de Mayo is a yearly celebration held on May 5 to celebrate Mexico's victory over the Second French Empire at the Battle of Puebla in 1862, led by General Ignacio Zaragoza. Zaragoza died months after the battle from an illness, and a larger French force ultimately defeated the Mexican army at the Second Battle of Puebla and occupied Mexico City. However, following the end of the American Civil War in 1865, the United States began lending money and guns to the Mexican Liberals, pushing France and Mexican Conservatives to the edge of defeat. At the opening of the French chambers in January 1866, Napoleon III announced that he would withdraw French troops from Mexico. In reply to a French request for American neutrality, the American secretary of state William H. Seward replied that French withdrawal from Mexico should be unconditional.

The Battle of Puebla, also known as the Battle of May 5 took place on 5 May, Cinco de Mayo, 1862, near Puebla de los Ángeles, during the second French intervention in Mexico. French troops under the command of Charles de Lorencez repeatedly failed to storm the forts of Loreto and Guadalupe situated on top of the hills overlooking the city of Puebla, and eventually retreated to Orizaba in order to await reinforcements. Lorencez was dismissed from his command, and French troops under Élie Frédéric Forey would eventually take the city, but the Mexican victory at Puebla against a better equipped force provided patriotic inspiration to the Mexicans.