Wandering around in Barcelona long ago, I was interested to encounter a street named after “11 de Setembre”, the 11th of September.
(I remember it being Rua de 11 de Setembre, but Google insists that it has never heard of such a street. Instead it wants to tell me about Rambla de 11 de Setembre, which seems to be quite far away from any part of Barcelona where I remember being. I don't know.)
That evening I asked my host, F.X. Noria, about it. (Thanks, Xavi! I had a great time!) He hastened to explain that it had nothing to do with the Sepember 11 attacks in the United States: September 11 had been the Catalonian national day since 1886.
I found the National Day of Catalonia (“Diada Nacional de Catalunya”) surprising. Many national days commemorate the gaining of national independence. For example, the U.S. national day commemorates the independence of the U.S. from the Kingdom of Great Britain. But Catalonia is not an independent country. Its national day commemorates the Siege of Barcelona in 1714, in which the last of Catalan independence was lost to the Spanish. Well, to the French guy who won the Spanish war of sucession. Catalonia had backed the other guy, who was Bohemian.
I like Diada Nacional de Catalunya because it gives me something better to observe on September 11.