King Momo or King Momos or King Momus, (Rei Momo in Portuguese or Rey Momo in Spanish) is considered the king of Carnivals in numerous Latin American festivities, mainly in Brazil and Colombia. His appearance signifies the beginning of the Carnival festivities. Each carnival has its own King Momo, who is often given the key to the city. Traditionally, a tall, fat man is chosen to fulfill the role because the original King Momo was of that physical stature.
In Argentina and Uruguay Rey Momo is more often represented by a big, sometimes monumental, doll made of papier-mâché over a wooden or wire structure. In these cases it is carried in a tow or at the top of a truck, and presides the carnival with a royal court of dancers. While a doll, it conserves its traditional features: flamboyant and colorful clothing, a smiling or joyful face and a prominent belly. It used to be burnt at the end of the festivities, also being its climax, but this practice is being discouraged in recent times for safety reasons.