Catalonia was invaded and annexed by Spain, but because of its wealth and its geographical position (it's an important port, or was at least) the Catalonians have been given special status and semi-autonomy.
On the other hand are the Basques, who are treated as second class citizens. This is why they seek independence. The Catalonians are treated well by the Spanish, so have no real desire to fight for independence.
“There are no boundaries in this struggle to the death. We cannot be indifferent to what happens anywhere in the world, for a victory by any country over imperialism is our victory; just as any country's defeat is a defeat for all of us.” – Che Guevara
“We still believe that the struggle of Ireland for freedom is a part of the world-wide upward movement of the toilers of the earth, and we still believe that the emancipation of the working class carries within it the end of all tyranny – national, political and social.” – James Connolly