Spain. The official language is Spanish, also called Castilian, and is the first language of over 72% of the population. Galician is spoken in the region of Galicia and Basque by increasing numbers of the population of Euskadi, the Spanish Basque Country. Catalan is spoken in Catalonia and the Balearic Islands, and the closely-related Valencian in the Valencia region. All these languages have official regional status.