Hello. I don't know english very well, so, sorry if my phrases aren't very corrects.
Mainly, Spain is a descentralizated country, whith the terrible problem of the separatists. Luckly, they aren't many people, but they are very represented in the parlament.
There are in Spain this regions (regiones, lands):
Cataluña, at the East of Spain. It's very powerfull economicly.
País Vasco, a very little place in the north of Spain, but with many independentists radicals people. They are powerfull economicly too.
Galicia, a very beautifull land in the north-west of Spain. They haven't separatists, however they have their own language.
Valencia, from where are the famous oranges. They speaks catalán (language of cataluña), but they aren't veru separatists. They are in conflict with Cataluña because they say that their language (Valenciano) is not catalán. At least, The governement of Spain consider that Valenciano and Catalán are de same language (But I don't think that).
I hope having help you.