What is de Las Casas trying to accomplish in this violent and gory letter?

In his letter, Bartolomé de Las Casas aims to expose the brutal treatment of Indigenous peoples by Spanish colonizers, advocating for their rights and dignity. By vividly detailing the violence and atrocities committed against them, he seeks to provoke a moral reckoning among his contemporaries and encourage reform in colonial policies. Ultimately, his goal is to defend the Indigenous populations and promote a more humane approach to colonization.