Arriving as one of the first Spanish (and European) settlers in the Americas, Las Casas initially participated in, but eventually felt compelled to oppose the abuses committed by colonists against the Native Americans. As a result, in 1515 he gave up his Indian slaves and encomienda, and advocated, before King Charles V, Holy Roman Emperor, on behalf of rights for the natives. In his early writings, he advocated the use of African slaves instead of Natives in the West-Indian colonies. In the 20th century, he has been criticized for being among the founders of the transatlantic slave trade. Later in life, he retracted this position, as he regarded all forms of slavery as equally wrong
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