The impression elicit by the title provides two interpretations: the adjective "last" indicates the interruption of continuity (there will be no more duchess), the possesive adjective "my" indicates the idea of possession, in line of aristocracy. The reader expects to read something about a missed love, broken by death for instance. The text is a dramatic monologue where the speaking voice is the main character, the duke (dramatis personae). The history develops following a scheme similar to soliloquy: the reader knows what characters think. The narrator is omniscient, so the reader knows about character's inner side.

Plot
The dramatis personae (the duke) is an historical figure, Alfonso duke of Este. He invites a messenger to visit his picture gallery, a closed space indoor of duke's castle. The invitation has something strange: during Reinassance English society was closed and the interactions between different classes were uncommon. To add, the duke shows a curtain covered fresco to the messenger, something he has never done with anyone else. The fresco is a portrait of her last duchess. The image figures a smiling and attractive woman. The portrait is the pretext used by the dramatis personae to reveal the duchess' story: she was duke's wife and she was desidered by many men, such as her servants they who give her symbolic presents (brench of charries). The intelligent reader asks himself two reasons: why does the duchess smile to everyone? And why a duke shows his gallery to a messanger? The duchess enjoys her wealth and her beauty, she was contended between many men different from her husband. The messenger understands this aspects while the duke explains him the duchess' story. The has been sent by the King, duchess' father. The duke is a King servant and invites the messenger as he represents the King.

Language
The language is symbolic. For instance servants offer to the duchess a brench of charries: charries are red, and red is allegory of passion and something prohibited. Also situations and backgorunds are allegories: the castle reminds to the typical Medieval background. The white horse becomes methaphor of duke's condition: the duchess ride the horse as she ride duke's wealth, she is using the duke. All things considered, the text  make a comparison between Reinassance and Medieval age: the evolution of human mind brings the awareness that God is not the only reality to face. Human has to face the contraddiction between the head and the heart. Poets try to reconcile aspects of human nature in Victorian Age.