A payment order confirms the attribution to the sculptor from Reggio nell'Emilia.
The room housing the renowned Dossi portraits of Ercole I and Alfonso I of Este in the house of Este art gallery also contains a male bust in Carrara marble, just over one metre high. It is recognised by critics as the only sculpture portraying Duke Ercole II of Este, and has been attributed to the Reggio Emilia artist, Prospero Spani Clementi (1516-1584) due to its style. Spani was well-known for his expressive style which had been borrowed from the language of Michelangelo. The first to investigate authorship of the work was Adolfo Venturi who attributed both the bust and the plinth carved with the anthropomorphic motto of Patience to Alessandro Vittoria. A proposal linking the plinth with Spani Clementi had actually already been made (Ferrari Moreni 1868) and subsequently the herm was also attributed to him (Magnani 1927). The sculpture arrived in Modena in 1629 from the Diamanti building store-room, and had originally been destined for the open gallery in the Patience room, in the northwest tower or Santa Caterina's tower in the Este castle. The duke was born in 1508 and ruled over Ferrara from 1534 to 1559. The sculpture shows him wearing an old-fashioned body armour decorated with a garland on the chest, comprising two branches of intertwined palms, flanked by a caryatid on each side. There is a small engraved cameo at the centre of the breastplate which does not show the feminine features of the personification of Patience, but the distinct
features of Saint Michael, acting as the heraldic reference to the Ordre de Saint Michel. This was a French order of knighthood that the duke had been a member of since 1528, when he received the honour from Francois I of Valois. Saint Michael is not the only thing that puts this wonderful marble sculpture into context, we also see Hercules underneath to the right as he holds the vault of heaven. This acts as an iconographic device leading us back to the complicated worldly undertakings of the duke of Ferrara. Just like the mythical hero, the Duke also had to shoulder the burden of governing a State whose very existence depended on the European geopolitical balance. Upon the death of his father in 1534, Ercole was aware of how his rule depended as much on good relations with the Holy See (legitimate owner of Ferrara) as with his links with Carlo V (Modena and Reggio were in fact imperial fiefdoms). In addition good diplomatic relations with Paris were also important. These were due to his close family ties with the French monarchy following his marriage to Renata di Valois (1528) daughter of King Louis XII and sister in law of Francois I, boosting the international prestige of the Ferrara court. We can therefore understand how Patience was considered to be the most important virtue in the house of Este, the main theme behind the iconographic project guiding the architectural restoration of the private areas in the Santa Caterina tower. The "room" or Patience room was the most prestigious area, and
emblematic of the castle after a fire had destroyed the residential area near the southeast tower in February 1554. The restoration of the pre-existing areas began in March of that year under the guidance of Girolamo da Carpi, and in April we have the first documentary references of the hitherto unknown presence of Prospero Spani in Ferrara. He would have come to present the duke with the recently completed marble bust, for which he was handsomely paid: one hundred golden scudos as noted in a hand-written note. The bust had probably been commissioned between the end of 1553 and the beginning of 1554. While not mentioned in the note, the engraved plinth with the allegory of Patience was an integral part of the sculpture, and it was definitely sculpted by the same chisel. While it may have come later, it would certainly have been before 3 October 1559 when Ercole II of Este died.