There is great argument about whether Catalonia was independent in the Middle Ages. The Crown of Aragon was independent. It included what is now Catalonia but that was only a part of it and outside the delirium of the Països Catalans the Crown of Aragon cannot now be reinvented. Catalonia itself may or may not have had an empire but what the Catalans did in the eastern Mediterranean caused more damage to Byzantium in ten years than the Turks had managed in the previous century. It can hardly be a source of pride for any sensible person.
But if as they say Catalonia was a nation, should it be, in the words of the Irish song, A Nation Once Again?
Even if Catalonia was once a nation, that fact, like those flowers that bloom in the spring tra la, has nothing to do with the case. One of the various things that Nationalist and Marxists share is a belief in the inevitable determination of history. But for liberals history is just what happens, one damn thing after another. History explains how we have got where we are, it can show us mistakes that we should avoid repeating, but it does not tell us what we should do in the future. Whether or not it makes sense for Catalonia to be independent in the EU (whatever that means) must be decided in the light of present circumstances, not from a romanticised view of the Middle Ages.