After the 1862 Battle of Puebla, the defeated French army retreated to Orizaba.
French forces had advanced inland from the port of Veracruz as part of France’s intervention in Mexico. Their defeat at Puebla on May 5 forced the French expeditionary army to withdraw toward Orizaba, a city in the mountains of Veracruz state. The retreat gave the Mexican government valuable time to strengthen its defenses.
The victory did not end the intervention. France sent a much larger force back to Mexico the following year, and French troops eventually captured Puebla after a long siege in 1863. They later occupied Mexico City and helped establish the Second Mexican Empire under Maximilian.
This is why Cinco de Mayo marks an important Mexican battlefield victory rather than the complete defeat of the French intervention.