Spain
As a percentage of the general population of all Spain, Spanish is natively spoken by 74%, Catalan by 17%, Galician by 7% and Basque by 2% of all Spaniards. Occitan is spoken by less than 5,000 people, only in the small region of "Val d'Aran".
Other Romance minority languages, though not official, have special recognition, such as the Astur-Leonese language ("asturianu", "bable" or "llionés") and Aragonese ("aragonés") in Aragon.
Castilians
Castilian (or Spanish) is the dominant language in Spain, and therefore was the language that was imposed in the New World by the Conquistadores during the Spanish colonization of the Americas. Due to this gradual process, the Hispanophone world was created. As Castilian was the language of the Crown, it became the official language of all Spain, used side by side with other languages in their regions for centuries. During the years of the Francoist State (1939 to 1975) there was an attempt to suppress the regional languages in favour of Castilian as the sole official language, causing a backlash against the use of Castilian in some regions after his death.