Supporters of Catalan nationalism marked the one-year anniversary since the unilateral declaration of independence in Barcelona on Saturday.
Protesters burned symbols of Spanish unity, including pictures of King Felipe VI and copies of the Spanish constitution.
Catalans have demanded that the Spanish Prime Minister confirm the result of last year's referendum and the official proclamation of independence.
Last year, Madrid imposed direct rule on Catalonia after it declared independence following a referendum. Efforts to split from Spain have since stalled, despite the election of a regional government in favour of secession.