Viggo Mortensen joins Òmnium Cultural, Catalunya pro-vote organisation

Mortensen, 59, born in New York to a Danish father and half-Canadian, half-US mother, is the latest and among the most famous of Òmnium Cultural's 115,000 members.

The actor, who played Aragorn in the epic fantasy series based upon Tolkien's bestselling series of novels, also signed up a year ago to the manifesto Let catalanes vote.

Òmnium Cultural fights to preserve the unique language and social culture of Catalunya, but goes a step further in pushing for its right to vote on whether or not to become an independent nation, something it strongly supports.

Other international stars who have clamoured for Catalunya's right to vote legally include former Baywatch star Pamela Anderson, along with Catalunya-born footballers Gerard Piqué, husband of Colombian pop-rocker Shakira, and Manchester City trainer Pep Guardiola.

Many supporters of the 'right to vote' do not actually agree with the idea of Catalunya's becoming an independent State, but believe the people should at least be allowed to participate in an advisory referendum to measure the depth of feeling, which could then be used as a tool to resolve the problems they have with Spain that lead them to want to secede.

“Welcome to the Òmnium family, Viggo Mortensen! It's an honour that you support this entity which works for culture, language and civil rights in Catalunya,” said a message on the group's Twitter site, featuring a photograph of the actor, who has starred in around 30 films since his début in 1985.

Romantically-linked to Spanish actress Ariadna Gil, his co-star on the Spanish production Capitán Alatriste, since 2009, Mortensen has starred in other Spanish-language films due to the fact he speaks the language fluently, as his entire childhood was spent living in Argentina and Venezuela.

He is an artist, photographer, poet and musician, and supports the Argentina-based football club, Atlético San Lorenzo de Almagro.

As the team's colours, blue and maroon, are the same as those of FC Barcelona, Viggo Mortensen was once assaulted by radical Real Madrid FC fans when he was based in the Spanish capital during filming.

Photograph: Òmnium Cultural on Twitter (@omnium)