Agustín Pío Barrios, later known as Agustín Barrios Mangoré, was a Paraguayan virtuoso classical guitarist and composer, born 5 May 1885 and died 7 August 1944 in El Salvador. Formally introduced to the classical guitar repertoire in 1898, he began composing seriously around 1905 and went on to write over 100 original works and some 200 arrangements, drawing on Paraguayan and broader Latin American folk music as well as Baroque and Romantic models. He toured extensively across Latin America, sometimes performing in traditional dress under the stage name Nitsuga Mangoré, and was among the first classical guitarists to make gramophone recordings.

Widely regarded — including by guitarist John Williams, who called him ‘the best of the lot, regardless of era’ — as one of the greatest guitarist-composers in the instrument’s history, Barrios expanded the guitar’s expressive and technical range well beyond the Spanish nationalist tradition. His magnum opus, La Catedral (1921), inspired by Bach and by hearing organ music in a Montevideo cathedral, remains one of the most performed and recorded works in the entire classical guitar repertoire.

Sources:

• https://en.wikipedia.org/wiki/Agustín_Barrios