It may interest you that private confession of Islam was legal under Franco, but public practice of Islam, or the building of mosques, was banned in Spain until 1989. All of this goes back to the Reconquista and the Inquisition in the late 1400s, when Muslims and Jews were forced to convert, synagogues and mosques were repurposed as churches (and not coincidentally, ham became the national dish). Franco's version of fascism was merely a continuation of that.
That being said, you can't practice Christianity or Judaism openly in Saudi Arabia to this day. Looking at it from Mecca, the point of origin of the Caliphates, to their furthest extent into Europe in Spain (or the Balkans) you can still see the traces of extremist religious bans existing on both sides. Jews tend to get caught in the middle and slaughtered at each turn, as they need to seek accommodations with whichever larger religion is in power in order to survive, and then are seen as enemies by the other one.
All this is written on the streets and buildings of Granada, Spain, where ancient Jewish stars adorn old buildings where there are no Jews, where the oldest church was once a mosque, and the Alhambra, symbol of the Caliphate and its civilization, is the largest tourist attraction in Europe... where the markets sell everything Arabic yet the day to day interaction of Muslims and Christians is fraught, each understanding very well their own history in the place. And where it is very, very strange to be one of the only Jews... with both Christians and Muslims hating you and claiming to protect you.