Why do you think the Spanish felt they had the right to force the indians to work for them?

The Indians weren't really human to them. They weren't Christian or "civilized." In addition slavery had been part of European life for centuries.

This is a subjective question. (aka opinion-based)

I am assuming you are talking about the Spanish in the Caribbean where slavery was most prominent in the 1500s.

Personally, I think the Spanish felt that they had the right to enslave the Indians because they did not view them as equals. Ironically, they were deemed as "savages" by the Spanish while the they themselves committed inhumane acts against the Indians. Conquest, torture, slavery, and disease devastated the native population. Another possible reason is their different religious views. Although the main reason for Spain's exploration to the "New World" was to find gold and resources, the Spanish had also brought missionaries along with the explorers. They had tried to convert the Indians to Christianity, but their differing views often led to warfare.

The Spanish felt they had the right to force the indigenous people to work for them due to several factors. One of the main reasons was the Spanish concept of "Encomienda," which was a legal and labor system implemented during the colonization of the Americas. The Encomienda system granted Spanish colonizers the right to demand tribute, labor, or goods from the indigenous people living in a particular area.

To understand this historical context, a good starting point would be conducting research on the Spanish colonization of the Americas and how they established their colonies. Examining primary and secondary sources like historical accounts, academic papers, or books can provide detailed insights.

Additionally, studying the Spanish colonial policies and ideologies, such as the Doctrine of Discovery or the concept of "civilizing missions," will help comprehend the mindset and rationale behind the Spanish actions.

Conducting research on the Encomienda system itself will provide a deeper understanding of the legal framework that justified the Spanish claim over the labor of the indigenous people. Exploring historical records such as legal documents, letters, or diaries from the time can shed light on the Spanish perspective.

By combining different sources and perspectives, one can gain a comprehensive understanding of why the Spanish felt they had the right to force indigenous people to work for them.