Catalan is not, as some believe, a dialect of Spanish, but a language that developed independently out of the vulgar Latin spoken by the Romans who colonised the Tarragona area. It is spoken by 9 million people in Catalonia, Valencia, the Balearic Isles, Andorra and the town of Alghero in Sardinia.

Variants of Catalan are spoken in Valencia and the Balearics, which were taken back from the Moors in the 13th century. According to Professor Albert Rossich of the University of Girona (Gerona) these variants reflect the origin of the people who repopulated these areas when the Moors were driven out. Valencia was repopulated with people from Lleida and Tortosa; the Baleares with people from Barcelona and l'Empordà in the north.

Catalonia had been an autonomous province within the kingdom of Aragón but when Aragón was united with Castile with the marriage of Ferdinand and Isabella, Castilian – ie Spanish – became the language of court and literature, while Catalan remained the popular tongue. When in 1714 Barcelona fell to Spanish troops led by the Earl of Berwick, Catalonia lost its autonomy, the central government imposed restrictions on the use of Catalan and Spanish became the official language.

It wasn't until the 19th century and the rise of the nationalist cultural movement known as the renaixença that Catalan was revived as a literary language, Rossich says. However, this revival was short-lived. The fascist regime that emerged triumphant from the civil war in 1939 did everything in its power to stamp out the official and private use of Catalan. Harsh penalties were imposed for speaking it.

The arrival of hundreds of thousands of immigrants from Spain's impoverished south further consolidated the use of Spanish as the lingua franca of Catalonia. Most of these immigrants, or their children at least, have come to understand and or speak Catalan since democracy was restored in 1978. However, large-scale immigration from Latin America over the past 10 years means just over half the Catalan population claim Spanish as their mother tongue.

Since the early 1980s, the imposition of a system known as "immersion," with Catalan as the only vehicular language in state schools, has guaranteed everyone educated in the past 30 years has a command of it. However, thanks to the presence of Spanish in daily life and the media, virtually all Catalans are perfectly bilingual.