To the contemporary reader, the term “Confessional poetry” is closely associated with the work of Sylvia Plath, but the term was first coined by M. L. Rosenthal in an article he wrote about Robert Lowell's Life Studies. In this article, he compared this more therapeutic and personal approach to poetry to the work written during the Romantic period. He also suggests that Modernist poets like T. S. Eliot and Ezra Pound are more recent precursors to Confessional poetry, saying Lowell is the first writer in this lineage to look upon a poet’s psyche without using indirection. “His speaker is unequiovcally himself, and it is hard not to think of Life Studies as a series of personal confidences, rather shameful, that one is honor-bound not to reveal.”
Confessional poetry, by Rosenthal’s description, is characterized by a sort of ghoulishness that comes from portraying a narrator in full. He calls Life Studies “impure art, magnificently stated but unpleasantly egocentric.”
Plath’s poems reflecting on her depressive tendencies and her relationships, in particular her poem “Daddy,” became significant examples of confessional poetry. So did John Berryman’s The Dream Songs, a series of unmetered sonnets written about a character named Henry who seems to act as a biographical conduit through which Berryman observes and explores his darkest thoughts and tendencies. This work outpaces the grotesqueness of Lowell’s work by presenting a character called Mr. Bones who is simultaneously a friend and a fractured version of the self and who speaks in verbal blackface, using a Southern dialect that would now be recognized as AAVE, African-American Vernacular English. This choice from a white writer would now be considered inappropriate, but it seems to have been chosen by Berryman as a technique for representing a fractured self.
Lowell also took his poetry from and allowed it to go to dark places to reflect his own complexities, his own moral gaps. Some of his book “The Dolphin” used and fictionalized letters written by his second wife. However, his writing does not break completely out of a distant poetic voice, as would the work of other confessional poets like Plath, Anne Sexton, or even Berryman. In Lowell's poetry, turmoil only occasionally breaks through—for example in his poem “Skunk Hour” where he describes the pain his mental illness causes him. In his poetry and in Confessional poetry at large, the readers are given a more direct and raw access to the mind of the narrator, undermining any romantic notions of how a poet thinks, feels, or acts.