In the case of the Aztec Empire, high inequality predates the Spanish–Aztec War; the richest 1% earned 41.8% of the total income, while the income share of the poorest 50% was just 23.3%

Income and inequality in the Aztec Empire on the eve of the Spanish conquest. Guido Alfani & Alfonso Carballo. Nature Human Behaviour, June 26 2023. https://www.nature.com/articles/s41562-023-01636-3

Abstract: Today, Latin American countries are characterized by relatively high levels of economic inequality. This circumstance has often been considered a long-run consequence of the Spanish conquest and of the highly extractive institutions imposed by the colonizers. Here we show that, in the case of the Aztec Empire, high inequality predates the Spanish conquest, also known as the Spanish–Aztec War. We reach this conclusion by estimating levels of income inequality and of imperial extraction across the empire. We find that the richest 1% earned 41.8% of the total income, while the income share of the poorest 50% was just 23.3%. We also argue that those provinces that had resisted the Aztec expansion suffered from relatively harsh conditions, including higher taxes, in the context of the imperial system—and were the first to rebel, allying themselves with the Spaniards. Existing literature suggests that after the Spanish conquest, the colonial elites inherited pre-existing extractive institutions and added additional layers of social and economic inequality.