In the Latin American colonial structure under the Spanish domination, the caste system stablished the rights and obligations of people based on the "pureness" of the blood. The scale went from the top, the Peninsulares, toi the black slaves at the bottom, with a lot of mixtures in the middle.
The Peninsulares were the ones living in the New World but born in Europe, they felt they were superior as they were not contamined with the vices found in America. They were in charge of the high office positions in church and state and were loyal to the Spanish crown. Belonging to this caste gave them a sense of higher humanity therefore an access to all kind of privileges.
The creoles were the ones with spanish blood, both parents were from Spain, but born in the New World. They were inferior because of this, being born in the New World somehow gave you less rights and made you impure, all the bad things related to the colonies were assosiated to them. The had office positions but could never reach the top.