Piero was not only a painter of great talent, but also a theorist and a mathematician, author of treatises on perspective and geometry. He was born in Sansepolcro, in the province of Arezzo, but it seems that his training took place in Florence. In 1439 he worked with Domenico Veneziano at the frescoes (now lost) in the church of Sant'Egidio. Piero went to Ferrara and Rimini. In 1452 the artist was taking part in one of the most important cycles of frescoes of the Renaissance, The Legend of the True Cross, found in the choir of San Francesco in Arezzo.
The Urbino Diptych was originally in the Audience Hall of Palazzo Ducale. It is painted on both sides and was probably joined by a hinge to be opened like a book. It arrived in Florence in 1631 as part of the inheritance of Vittoria della Rovere, wife of Grand Duke Ferdinad II. The painting shows the Duke and Duchess facing one another in solemn profile as on a classical medallion. The extremely detail representation is typical of Flemish arte. The painting is very realistic, showing for instance the Duke’s broken nose. The background landscape is treated with an almost miniaturist technic. It might evoke the territory at Montefeltro, Federico’s land. There are curtains or windows, but a magnificent birt’s - eye view unites the perspective of two panels.
The two scenes on the back with allegorical chariots symbolize the moral values of the two characters. Each of them is solemnly accompanied on the chariot by four virtues. Battista Sforza travels with the theological ones: Faith, Charity, Hope and Modesty. Federigo is accompanied by the cardinal virtues: Prudence, Temperance, Fortitude and Justice. The chariot of Battista is drawn by two unicorns, symbol of purity and marital fidelity. Their reins are held by a little angel. The landscape in the background maybe that of the Valdichiana. On the other panel a winged Victory crowns Federigo. The lake in the background is probably Trasimeno. The two paintings on the back have probably been created after 1472.
On the classical style marble under the chariots are inscriptions in Latin. Below Battista’s representation the inscription reads: “She who was able to retain moderation in favorable times flies on the mouths of all men, adorned by the praise of her great husband’s undertakings”.
Below Federigo’s triumphal chariot is written: “He who the undying fame of the virtues proclaims worthy to hold the scepter, peer of the greatest condottieri, the illustrious one is carried in grandiose triumph”.