In his early studies for the Sforza monument, Leonardo repeated the motif of a rearing horse that he had painted so successfully in the Adoration of Magi.
After 1489, when Sforza apparently decided to increase vastly the size of the monument, Leonardo changes its positioning. In this sketch, he draws a more conventional walking gait with the bent right foreleg raised.
In 1492 Leonardo was laying plans for casting the new enlarged horse. This sketch portrays a walking horse mold enclosed by three braces.