Tropicalia was one of Brazil's largest cultural movement that arose in the 1960s as a result of the avant-garde period that criticized the 1964 coup d'etat. The movement took on various forms including theatre and poetry, however music was the largest component.
The popular and respected artists at the time were part of making the manifesto happen and grow, which included the likes of Caetano Veloso, Gilberto Gil and Tom Ze to name a few. Their style fused traditional Afro Brazilian sounds, foreign Rock n Roll and Psychedelic sounds. Their lyrics described Brazilian society as they saw it, often using a satirical approach. The album which acted as the musical manifesto was 'Tropicalia: ou Panis et Circencis.' It employed the signature Tropicalia techniques of unorthodox song and time structures, and criticized the coup. Even to this day, artists like David Byrne and Beck have cited Tropicalia as an influence in their work.
For more on the genre, check out the 'Brazil Classic' episode that showcases this period of Brazilian music here.