The Spanish Civil War (1936-1939) and the post-war period were black for improvisation, seen as suspicious separatism activity to the Francoist authorities. During those years Basarri, along with Uztapide, was one of the improvisers who kept alive this activity during the feasts of the small rural towns in the Spanish Basque Country.
One can consider Basarri on the one hand as the main improviser, along with Uztapide, who served as a bridge between the pre-war generation and the one that appeared in the last years of the Franco regime. On the other hand he was one of the first theorists of improvisation, which introduced the improvisation in theaters.
Parallel to his work as bertsolari, Basarri was a journalist. In the Basque Country (and especially in Guipúzcoa), he was a well known radio and newspaper journalist, writing articles in both Basque and Castilian. His work as a journalist used to be primarily focused on the world of Basque rural culture.