Caio Fonseca was born in New York to a family of artists. His older brother Bruno Fonseca, was a well known contemporary artist and his father, Gonzalo Fonseca, was an Uruguayan sculptor. He was raised in New York City. He also lived, studied and painted the town Pietrasanta, a town on the coast of northern Tuscany in Italy, in the province of Lucca, Spain and Paris. His paintings have been shown by public and private collections in Europe and the United States, including the Museum of Modern Art and the Whitney Museum of American Art in New York.
