Agustín Pío Barrios Pereira, born on May 5, 1885, in San Juan Bautista, Paraguay, was a renowned Paraguayan classical guitarist and composer, celebrated for his virtuosic performances and prolific compositions. Barrios, who was of indigenous Guaraní descent, was deeply influenced by Paraguayan folk music, which he skillfully integrated into his diverse compositional style. He began playing the guitar at a young age and was introduced to the classical guitar repertoire by his teacher, Gustovo Sosa Escalada. At fifteen, he attended the Colegio Nacional de Asunción, becoming one of the youngest university students in Paraguayan history.

Barrios composed over 300 works, including notable pieces such as "La Catedral" and "Julia Florida." His compositions are often categorized into folkloric, imitative, and religious styles. In the 1930s, Barrios adopted the pseudonym Nitsuga Mangoré and occasionally performed in traditional Guaraní attire, honoring his cultural heritage.

Throughout his career, Barrios was acclaimed for his remarkable live performances and early gramophone recordings. His music gained international recognition through recordings by artists like John Williams. Barrios passed away on August 7, 1944, in San Salvador, El Salvador, leaving a lasting legacy as one of the most significant figures in the classical guitar world.