After receiving his training from Gustavo Sosa Escalada, Barrios left Paraguay for one week of concerts in Argentina.
He was so successful that he toured for 14 years. In 1934 he went to Europe to perform, becoming the first Latin-American guitarist of stature to do so. His performances have been compared to Segovia for their interpretation and to Paganini for their virtuosity. Barrios composed over 300 works, many of which he attributed to obscure early composers in the hope that this would allow them to be regarded seriously. Some of his pieces are now in the repertory (Danza paraguaya and El catedral) and many more would be, if not for his carelessness in publishing them. He was the first classical guitarist to make a gramophone recording.