Historian Peter Gerhar mentions that Actopan was first visited by the Spaniards before the conquest was consummated, at the end of 1519 or beginning of 1520. By 1521 the indigenous people of the area and other nearby parts, participated in the defense of the territory under the command of the tlatoani Cuauhtémoc against the Spanish conquerors. On August 13, 1521 Tenochtitlan fell to the troops of Hernán Cortés and his allies. Between 1521 and 1524, a certain political-military control was established in almost all the territories subject to the Mexica empire, including Actopan.
