rei momo, or king momo, is the king of carnival and has been appearing in brazilian carnivals since 1933, when the first king momo was chosen to appear during the carnival in rio de janeiro.

at that time, the journalist morais cardoso was elected and held the position until his death in 1948.

this innovation in the merrymaking was much enjoyed and several other brazilian cities have since adopted a king momo for their carnivals.

carnival is officially opened when king momo, wearing the traditional costume for the occasion, is crowned on the friday of carnival.

in a televised event, the mayor of rio de janeiro hands over the key to the city, a huge gold key covered in glitter, and for the five days of carnival king momo symbolically runs rio de janeiro.