Spain (under Ferdinand and Isabella) forbade the enslavement of Indians in the New World very early on, probably after various educated Indians were brought back to Spain by the religious orders that had educated them and revealed themselves to be the equal of any Spaniard.
Papal bulls also forbade slavery in general; all persons who were bought (usually from Arab slave traders) were essentially indentured servants, and had to be allowed to buy their freedom or manumission had to be allowed at the discretion of their owners (usually upon death, in their wills), and they had to be allowed to marry, have families and receive religious education. The Spanish accepted the Bulls and that is why you have complicated 16th-17th century paintings in Mexican museums showing the various degrees of lineage (European, Indian and African) that were used to classify people.
For some reason, the Portuguese completely ignored the Papal Bulls and were some of the worst slave traders and abusers of African slaves in the Western hemisphere, something that still leads to problems in Brazil, which has a heritage of resentment.
Spain (under Ferdinand and Isabella) forbade the enslavement of Indians in the New World very early on, probably after various educated Indians were brought back to Spain by the religious orders that had educated them and revealed themselves to be the equal of any Spaniard.Upon his return from his first voyage, Columbus sold the Spanish crown on colonization based on the native population which he portrayed as a ready slave labor force. The reason African slaves were imported by the Spanish is that disease knocked off so many of the natives so quickly. "Indians" were enslaved and forced to work in mines in Peru.