Cinco de Mayo is a widely recognized holiday celebrated for its vibrant dances, colorful decorations, and traditional Mexican cuisine. While it is celebrated in both Mexico and the United States, the festive occasion commemorates a significant Mexican military victory from 1862. Surprisingly, the holiday's popularization and early celebrations largely took shape in America, rather than Mexico.

The historical backdrop to Cinco de Mayo dates back to 1861, when Mexican President Benito Juárez declared a temporary halt on foreign debt payments. This decision led France, England, and Spain to dispatch military forces to Mexico. Although England and Spain eventually withdrew their troops, France, under the command of Napoleon III, pursued an ambitious agenda to establish a monarchy in Mexico, with Maximilian of Austria as its emperor. This French endeavor was strategically aimed at curbing U.S. influence over North America and expanding French regional power, particularly while the United States was embroiled in its own Civil War, thus weakening its capacity to intervene.

On May 5, 1862, a pivotal event occurred: the Battle of Puebla. An outnumbered and less equipped Mexican force, consisting of an estimated 2,000 to 5,000 soldiers, achieved a remarkable victory against a much larger 6,000-soldier French army. This triumph, spearheaded by Mexican General Ignacio Zaragoza, became known as the Battle of Puebla. While France maintained some control over Mexico until 1867, this early success served as a powerful symbol of the nation's struggle against foreign dominion and significantly boosted national morale.

The widespread news of Mexico's victory in the Battle of Puebla quickly resonated with Mexican-American immigrants living in California. Organizers there seized the moment to rally support for Mexican resistance against French rule. As California State University Channel Islands professor José Alamillo explained, Latinos in California began to raise funds for Mexican troops and established a crucial network of patriotic organizations. By 1863, Mexican Americans in California were already commemorating the date, imbuing it with political and cultural significance tied to resistance and democracy.

The strong ties between many American citizens and Mexico at the time further fueled these celebrations. The Mexican-American War (1846-1848) had resulted in Mexico ceding vast territories—Arizona, New Mexico, California, Nevada, and Utah—to the U.S., granting immediate U.S. citizenship options to their inhabitants. Furthermore, the Texas Revolution had paved the way for Texas to become a U.S. state, rather than remaining part of Mexico. Consequently, many people residing in America during the Battle of Puebla had recently been Mexican citizens, making it natural for a Mexican victory to deeply resonate with Mexican-American communities.

One of the earliest documented Cinco de Mayo celebrations took place in Los Angeles and San Francisco on May 27, 1863, featuring music and parades to honor the victory. These festivities were subsequently moved to May 5 the following year. Over the subsequent century, the meaning of Cinco de Mayo continued to evolve. In the 1960s, it gained new significance in the United States, transforming into a broader celebration of Mexican culture, pride, and identity.