Browning's "My Last Duchess" is partly an important poem because of its unusual point of view. The poem is told using first person, which means that the readers should be able to closely access the narrator (the Duke) and his thoughts. However, despite the fact that the poem uses first person, we eventually learn that the poem is only telling part of the story, and that the Duke is perhaps not the most reliable narrator. Critics typically discuss the ways that Browning brilliantly layers complex hidden meanings beneath the surface of the Duke's perspective. Browning carefully crafts the poem so that, while the Duke says one thing, readers can infer multiple other meanings.
Critics also praise this poem for being historically accurate in its depiction of the Duke as a power-hungry, arrogant, and misogynistic aristocrat. During a time when women had much less power and freedom than they do now, Browning gives us a poem that could be seen as a protest against domestic abuse, the mistreatment of women, and the abuse of power against those with less power and less rights.