Those colonies with their fertile soil and extensive mines of gold and silver, were crown property. And Charles the Fifth, who wore the Spanish crown at that time, could not long withstand the temptation to reduce the aborigines to a state of vassal-age, and compel them to work their own soil and dig in their own mines for his benefit. He did thus reduce them to slavery. Tytler's Mod. His. part II. sect. 41.
Slavery had its origin simultaneously with the conquests of this continent, and was invented by that same plundering, bloody and murderous spirit which characterised those conquests.
In process of time an effort was made to effect the abolition of aboriginal slavery ; but Charles the Fifth was so elated with his royal patent of property in man, that when the abolition delegate plead the cause of the aborigines before him, he turned the damper of both ears, indicating that he had not the beginning of a notion to entertain the prayer.