The idea for the equestrian monument came from Galeazzo Maria Sforza, who conceived of a life-size sculptural group that would represent his father Francesco astride a rearing horse.

Later on, the project was taken up again by Ludovico il Moro, who commissioned Leonardo to sculpt the monument. Between 1489 and 1490 the project was changed; the dimensions were almost quadrupled and the idea of a rearing horse was abandoned in favor of a horse in a walking pose.