Duke of Ferrara
A dramatic monologue reveals more about the speaker than about the subject, so the duke's personality is the true subject of the poem. In his words he reveals he is wealthy, has a deceased wife, and is seeking a new wife. The duke is the "only one" to open the curtains that cover the late duchess's portrait, indicating he is a controlling man. He has a long family history (a 900-year-old name), and he is arrogant, choosing never to "stoop."
Duchess of Ferrara
The duchess, according to her husband, was easily made happy, enjoyed nature, riding her mule, and his presence. She did not, however, enjoy his presence more than everything else. In his monologue this is presented as a shortcoming.
The marriage broker is negotiating on behalf of an unnamed count who wants his daughter to be the next duchess. During the discussion, the duke invites the marriage broker to see his private art gallery. There hangs a portrait of the last duchess, now deceased. The broker sits on a bench to view the painting as the duke describes its creation and the fate of the duchess. Afterward, the pair go back downstairs to continue their negotiations.