Honoured and admired by his generous patrons in Milan, Charles d’Amboise and King Louis XII, Leonardo enjoyed his duties, which were limited largely to advice in architectural matters. Tangible evidence of such work exists in plans for a palace-villa for Charles, and it is believed that he made some sketches for an oratory for the church of Santa Maria alla Fontana, which Charles funded. Leonardo also looked into an old project revived by the French governor: the Adda River that would link Milan with Lake Como by water.

During this second period in Milan, Leonardo created very little as a painter. Again Leonardo gathered pupils around him. Of his older disciples, Bernardino de’ Conti and Salai were again in his studio; new students came, among them Cesare da Sesto, Giampetrino, Bernardino Luini, and the young nobleman Francesco Melzi, Leonardo’s most faithful friend and companion until the artist’s death.

An important commission came Leonardo’s way during this time. Gian Giacomo Trivulzio had returned victoriously to Milan as marshal of the French army and as a bitter foe of Ludovico Sforza. He commissioned Leonardo to sculpt his tomb, which was to take the form of an equestrian statue and be placed in the mortuary chapel donated by Trivulzio to the church of San Nazaro Maggiore. After years of preparatory work on the monument, for which a number of significant sketches have survived, the marshal himself gave up the plan in favour of a more modest one. This was the second aborted project Leonardo faced as a sculptor.