It was organized by the Catalan National Assembly (ANC), the main civil society organisations behind the massive pro-independence demonstrations held since 2012, and Òmnium Cultural.

[2] The number of participants that took part in the demonstration was 45,000 according to the Police Bruxelles Capitale Ixelles.

Representatives from a pro-independence pressure group handed over a petition with 25,000 signatures to the European Parliament.

The manifesto delivered by members of the Committees for the Defense of the Republic calls on the European Union to act to achieve «the release of the political prisoners».

[6] The event included the participation of Catalan President Carles Puigdemont and members of Together for Catalonia, Republican Left of Catalonia–Catalonia Yes and Popular Unity Candidacy.