The term peninsular was used to describe someone who was born on the Iberian Peninsula and lived in New Spain. In the Spanish caste system, peninsulares were favored over Spaniards born in America. These people were called criollos.
People born in Iberia had stronger connections with people on the Spanish Court. As a result, they received more military and administrative appointments in New Spain. Despite their equal status under Castile laws, peninsulares enjoyed a higher social status than criollos, leading to competition between members of both groups. The social distance between peninsulares and criollos eventually diminished because of harsh frontier conditions.