Final answer:
Las Casas' efforts to protect Indians had limited success due to local officials in Spanish colonies ignoring new laws established by the Spanish Crown.
Step-by-step explanation:
Bartolomé de las Casas, known for championing the rights of the Indians, saw limited success in his efforts partly due to local officials in Spanish colonies ignoring the new laws designed to protect the natives. Las Casas, initially an encomendero and participant in the exploitation of native peoples, had a profound change of heart. By 1542, fueled by his relentless advocacy, the Spanish Crown issued the New Laws of the Indies for the Good Treatment and Preservation of the Indians, which aimed to dismantle the encomienda system. However, the local officials, whose power and wealth were intertwined with the encomienda system, largely ignored these regulations, allowing the mistreatment of the Indians to persist. Despite Las Casas' significant influence on bringing the issue to light, the challenges of enforcing these laws across distant and autonomous colonies remained substantial.