Complex sentence: The indigenous peoples could not be enslaved because they were legally subjects of the Spanish Crown and to protect the indigenous peoples, several forms of land ownership and regulation were established: "resguardos", "encomiendas" and "haciendas".
Split into simpler sentences: The indigenous peoples could not be enslaved because they were legally subjects of the Spanish Crown. To protect the indigenous peoples, several forms of land ownership and regulation were established: "resguardos", "encomiendas" and "haciendas".