Why did allies help Cortes defeat the Aztects?

Allies helped Hernán Cortés defeat the Aztecs for several reasons, including resentment toward Aztec domination and tribute demands from surrounding tribes. Many indigenous groups, such as the Tlaxcalans, viewed the Spaniards as potential liberators who could help them overthrow the oppressive Aztec rule. Additionally, Cortés promised these allies land, wealth, and an opportunity to establish their own power in the region, which motivated their support in the conquest.