"Gallego" the language of Galicia
Despite the fact that every Galician you are ever likely to encounter will speak regular Spanish ("Castillano"), the native tongue of this region is "Gallego" (also spelt "Galego").
Gallego should not be confused with being a dialect or regional accent because it is not. It is in fact one of four distinctive languages spoken across Spain's various population masses and it is now promoted and supported by the Galician and Spanish governments.
Although banned during General Franco's dictatorship of Spain, the tongue of "Gallego" is both widely spoken and taught in schools throughout Galicia. About three million inhabitants of Spain currently speak it and there are large populations in Argentina and other South American countries who also converse in this regional language.
Historically, Gallego had its origins in the 12th century, when it appears to be almost identical to Portuguese, but since then it has diversified and taken on a distinctive feel, enabling it to be classified as a unique tongue in its own right.
When General Franco came to power he, as with most dictators, saw a vision of a totally unified nation, devoid of local differences and speaking the same language. To this end he stopped the teaching of Gallego in schools and removed it (in written and spoken form) from all public arenas. His motivations were envisioned to make Spain stronger, but they also removed the regional identity that is a part of Galicia and, upon his demise, Gallego returned. Surprisingly, the current leader of the Xunta (Galician parliament) and staunch promoter of Gallego was once in Franco's government - but that's politicians for you.
Today, Galicia has its own TV channel which broadcasts solely in Gallego and there are an estimated one thousand new publications in "gallego" each year. There is also an official body called the “Irmandades da Fala” who protect and promote the "gallego" idiom. The "Xunta" (or parliament of Galicia) also actively encourage its use in everyday business and social life.
More information on Gallego
If you want to find out more about the idiom of Galicia - "Gallego", check out this link: