During the summer of 1944, Max Ernst, fellow artist Dorothea Tanning, and renowned art dealer and collector Julien Levy rented a house on the Great River of Long Island. It was during this period that Ernst created the plaster version of Moonmad. Levy later recalled how he helped to place the work in a field of hayweed and shrubs so that Ernst could look at the sculpture under the illumination of a full moon; it was perhaps this experience that gave the work its title.