The three causes for the proliferation of slavery by Spain against the Apaches and associated tribes includes delay, undercompensation and unenforceabilty. Delay refers to the physical delay of the Queen’s wishes to the New World, which may have taken a calendar year to receive let alone enforce or implement. Second, life on the frontier was harsh for the Spanish pioneers and the extra money from the slave trade made it slightly more worth it. Lastly, the pragmatic ideals of Queen Isabella were not practical from the perspective of leaders in the region, and were lip serviced but de facto ignored.
The slavery framework appears to be a balance of kinship and chattel. Spaniard captives were more integrated into tribes, but were generally bought and sold just like the Spaniards operated the principles of chattel on Native Americans. Hereditary slavery is not discussed, but the examination of this period was too small to draw a definitive conclusion. Slaves were not natally alienated by the Spanish until the mid-18th century which violated the old-school encomienda. This was out of rare fear instead of labor imbalance. The West Indies had extremely high slave to freemen ratios that fostered rebellion and eventually came very dangerous for the plantation management.
I wonder what the ratios were in New Mexico.
In one sense, religion acted as a carrot for the Native American to a better life. It also offered a rationalization for a servant of God to just be an indentured servant for God. The threat of enslavement was used from a position of leverage, and skirmishes were initiated by Spaniards as agent provocateurs to generate war captives for enslavement, sometimes via backroom deals to more powerful tribes. Many years after Cerrato, priests in the New Mexico region were bent on purchasing slaves despite the theoretical legal ramifications.
The presence of a foreign power on the Natives’ soil may have caused additional hardship, which caused additional and unforeseen debt, requiring otherwise solvent tribe-members to sell family members into catechism. Parallels to the drug trade exist, discussed elsewhere. Ultimately, the goal was colonization or increase of Christians for Queen Isabella (just like the reduction of communism or increase of capitalism for the Contras in Nicaragua etc.). Slavery, like cocaine, was just too profitable to not get a cut, especially considering the triumvirate of problems first mentioned in this discussion.
Cuervo and Morgollon issued writs allegedly making the practice more illegal, but a crisis was brewing. The other tribes in the west were consolidating and becoming more powerful, and a threat to land. Slavery came second to survival, until an accidental detente was reached. Please correct me if I am wrong, but essentially the Spanish and Comanches / Utes reached a power equilibrium during the mid-18th century. Slaves that were caught were sent elsewhere in the Spanish kingdom, namely Mexico.