In November 1916, a young Afro-Brazilian musician named Donga registered sheet music for the song "Pelo telefone" ("On the Telephone") at the National Library in Rio de Janeiro. This apparently simple act--claiming ownership of a musical composition--set in motion a series of events that would shake Brazil's cultural landscape. Before the debut of "Pelo telephone," samba was a somewhat obscure term, but by the late 1920s, the wildly popular song had...