San Juan de Ulúa, now known as Castle of San Juan de Ulúa, is a large complex of fortresses, prisons and one former palace on an island of the same name in the Gulf of Mexico overlooking the seaport of Veracruz, Mexico. Juan de Grijalva's 1518 expedition named the island. On March 30, 1519, Hernan Cortés met with Tendile and Pitalpitoque, emissaries from Moctezuma II's Aztec Empire.

The Mexican War of Independence was an armed conflict and political process resulting in Mexico's independence from the Spanish Empire. It was not a single, coherent event, but local and regional struggles that occurred within the same period, and can be considered a revolutionary civil war. It culminated with the drafting of the Declaration of Independence of the Mexican Empire in Mexico City on September 28, 1821, following the collapse of royal government and the military triumph of forces for independence.