Yes, Spain did control the Incas and Aztecs for gold so he could promise the Spanish for the gold. (He promised them thats why he took over)
Cause & Effect: The cause of the Encomienda system was the Spanish crown offering land and Indian slaves to conquistadors going to the new world. The effect was heavy depopulation of Indians from brutality and disease leading into African slaves becoming a new labor force. You just studied 15 terms!