  Political identity is often manifested in language variation, but the
relationship between the two is still relatively unexplored from a quantitative
perspective. This study examines the use of Catalan, a language local to the
semi-autonomous region of Catalonia in Spain, on Twitter in discourse related
to the 2017 independence referendum. We corroborate prior findings that
pro-independence tweets are more likely to include the local language than
anti-independence tweets. We also find that Catalan is used more often in
referendum-related discourse than in other contexts, contrary to prior findings
on language variation. This suggests a strong role for the Catalan language in
the expression of Catalonian political identity.
