Languages of Catalonia
The main cause of Spanish and Catalan social bilingualism in modern Catalonia was large-scale migration from the rest of Spain during the 20th century, as Catalonia started a significant industrialization which demanded an increased workforce from elsewhere. Spanish has historically been spoken among a minority of civil servants born in other regions in Spain and among segments of the wealthiest bourgeoisie. Spanish has also been spoken as a second language by most Catalans, as it has been the only official language over long periods since the eighteenth century.
Languages of Catalonia
Catalan has enjoyed special status since the approval of the Statute of Autonomy of 1979 which declares it to be the language "proper to Catalonia". Spanish had been the only official language for most of the period between the 18th century and 1975.