Rio de Janeiro’s first official samba-school competition was held in 1932.
The competition was organized by the newspaper Mundo Sportivo and took place at Praça Onze, a central area strongly associated with early samba. Escola de samba groups had already developed in Rio, but the 1932 event gave them a formal public contest.
Mangueira won that inaugural competition. The event helped establish the parade format in which schools present a samba-enredo, coordinated costumes, floats, percussion, and large dancing contingents. Later competitions became more structured and moved through several venues before the Sambadrome opened in 1984.
The 1932 contest is sometimes confused with the founding dates of individual samba schools, which are earlier or later. It refers specifically to the first official citywide samba-school competition, not the beginning of Carnival in Rio or the creation of samba itself.