The idea of offering up people as sacrifices was quite unsettling to Cortes (Livescience). Because of this factor, he was successful in forming alliances with several other Indian tribes. Cortes and his troops received assistance from many different Indian tribes during their conflict with the Aztecs.
After suffering a string of setbacks at the hands of the conquistadors, the Tlaxcalans ultimately chose to negotiate a peace treaty with the Spanish and form an alliance with them in order to combat the Tlaxcalans’ old foes. The assistance that Cortes received from the Tlaxcalans was ultimately going to prove to be very important for his campaign.
As we have seen, the answer is a combination of two primary causes: the introduction of Castellan swords and diseases brought by the Spanish, against which the Mexica had neither an immunity nor an effective cure; in addition, there was a third, more important cause, which was the successful military strategy of the Spanish and their alliance with other local Aztec tribes.
Cortes’s army were victorious in the battle, and he sent the Spanish soldiers who had survived back to Tenochtitlan with him to use as reinforcements.During Cortés’ absence, Alvarado caused additional anger among the Aztec people by ordering the execution of hundreds of Aztec nobility at a ceremonial feast.This led to the death of Cortés.The people who lived in Tenochtitlan urged that the Spanish be expelled from the city.