Modeled after Alfonso II, the fifth and last Italian duke of the principality of Ferrera, which later became part of the Papal states, the proud, possessive, and selfish Duke of Ferrera is a great lover of art, a dilettante. In Browning's dramatic monologue, the duke pulls a curtain to display a frescoe of his deceased wife. Redefined as an art object by the duke, the life of the Duchess is discussed by the duke as though it were a composition of art:
The dropping of the daylight in the West,
The bough of cherries some officious fool
Broke in the orchard for her, the white mule
She rode with round the terrace--
So, when the duke points to the statue of Neptune as he and his guest descend the stairs, it is as though this arrogant dilettante draws his guest's attention to yet another work of art. But, while the duchess is painted onto the wall, this new exhibit is a sculpture, and a concluding piece to the tour of the duke's objets d'art.