The Medici family wanted to build the Medici Chapels in the basilica of San Lorenzo, considered their private church, as a mortuary in which to bury the most illustrious members of the family.
Work on the Medici Chapels began with Michelangelo in March of 1520 and was terminated in 1546 by Giorgio Vasari, after Michelangelo left Florence to return to Rome.
In the mortuary, Lorenzo the Magnificent, his brother Giuliano, Lorenzo Duke of Urbino and Gìuliano Duke of Nemours (two Magnificents and two Captains), all were to rest in peace.
The tomb of Lorenzo Duke of Urbino, who was referred to by Vasari as "il Pensieroso" or "the Melancholy", is found on the left of the altar: beneath him the figures of Crepuscolo and Aurora.
Farther beneath lays the tomb of Giuliano with the staff of command in hand with underneath Night and Day.
Above the stone coffins of the two Magnificents one can admire the statue of the Virgin Mary done by Michelangelo in 1521.
Aside it stands the two protective saints of the Medici family, on the right Cosimo, done by Montorsoli in 1537 and on the left Damiano, opera of Raffaele of Montelupo in 1531.