The Duke is obviously proud and very concerned with his own importance and nobility. It is the Duchess' friendly behavior that really irritates him because it elevates others to his equal footing:
"as if she ranked
My gift of a nine-hundred-years-old name
With anybody's gift. Who'd stoop to blame
This sort of trifling?"
The Duke says that he is not a good speaker --- "Even had you skill/In speech—(which I have not)" --- but he speech to the emissary shows he clearly does have very good speaking skills. This lets us know that he can lie easily when it suits his will, and that he is not a man to be trusted.
The Duke also show his pride, and even more so, his need to absolutely control every situation. He speaks of how he might have handled the situation with her, suggesting he could have talked to her. However, to have talked to her would have been to let go of some control, and he refuses to. See the lines below.
However—and if she let
Herself be lessoned so, nor plainly set
Her wits to yours, forsooth, and made excuse,
—E'en then would be some stooping; and I choose
Never to stoop.
Finally, the Duke shows that he is vindicative and tyrranical. He will get his own revenge to make sure it is clear who has the power. He says:
I gave commands;
Then all smiles stopped together.
The duke is a very proud, vain and egotistical lord who views his ex-wife as an object or "trophy" rather than as a person. Super-macho and so blasé as to not even be aware of it, he takes pride in showing his house guest various family heirlooms, among them being her portrait done by a reputed artist named Fra Pandolf. The duke evidently wants to show off his wealth, his acquisitions, and his elitism, flounting the fact of having rubbed elbows with such famous people. In the same breath he "dumbs down" his first wife and decrees her as unworthy - as if her banishment reinforces his own superiority:
There is no need to think that the Duke is conscious of his implications: given his excessive pride, his refusal ever to stoop, he could hardly tolerate allowing another to believe his Duchess unfaithful to him, especially through his own revelation, however subtle.
Through his comments, the guest (the reader) also takes a guided tour through the duke's twisted soul and warped value system. For instance, he avows having taken offense at the first duchess's simple joy of living and a blush appearing when she posed for the portrait ("a spot of joy on her cheek"), suspected infidelity and "treason" when no real justification or proof of it was there. Dispensing with her, he moves on to take another conquest, a new wife who will supply the obsessive fawning demanded by his super ego:
As he believes is only his right, the Duke attempts to acquire another Duchess who will respond solely to him, and to that end he tells his last Duchess's story. In so doing he reveals a colossal ego. But through his very skill in speech he betrays that ego, for his subtle and unconscious slander of his last victim exposes at bottom an instinctive self-justifier, or at least a man predictably insecure behind a tyrant's swagger.
The final "crunch" comes when he turns abruptly from this subject to admire a statue another artist has recently cast for him, am image of Neptune taming a sea-horse. In truth, the statue embodies his own concept of domination, especially over women. He finishes as he starts, contemplating his own power, his refined artistic taste, his superiority.
In short, a V.I.P. to be venerated and admired!
I want to address the character traits of the Duke as he portrays himself throughout.
I feel these three characteristics, would be the easiest to convey.
Department of English
Bangladesh University of Business & Technology