"Confessional Poetry" (From Wikipedia):
Confessional poetry traffics in intimate, and sometimes unflattering, information about details of the poet's personal life, such as in poems about illness, sexuality, despondence. The confessionalist label was applied to a number of poets of the 1950s and 1960s. John Berryman, Allen Ginsberg, Robert Lowell, Sylvia Plath, Theodore Roethke, Anne Sexton, and William De Witt Snodgrass have all been called "Confessional Poets." As fresh and different as the work of these poets appeared at the time, it is also true that several poets prominent in the canon of Western literature, perhaps most notably Sextus Propertius and Petrarch, could easily share the label of "confessional" with the confessional poets of the fifties and sixties.
Development of definition
In 1959 M. L. Rosenthal first used the term "confessional" in a review of Robert Lowell's Life Studies entitled "Poetry as Confession,"  Rosenthal mentions earlier tendencies towards the confessional but notes how there was typically a "mask" which hid the poet's "actual face." "Lowell removes the mask. His speaker is unequivocally 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."
Life Studies broke new ground: the reviewer in The Kenyon Review saw clearly what new thing had been achieved: "For these poems, the question of propriety no longer exists. They have made a conquest: what they have won is a major expansion of the territory of poetry." Nevertheless there were clear moves towards the confessional mode before the publication of Life Studies. Delmore Schwartz's Genesis had been published in 1943, and John Berryman has written his Sonnets to Chris in 1947, although they were not to be published until 1967 (and then as Berryman's Sonnets). Berryman's sonnet sequence fits in the long tradition of highly personal sonnet sequences, stretching back through George Meredith's Modern Love to William Shakespeare's sonnets and the sonnets of Petrarch. The difference between the long tradition of intimate, personal, lyrical poetry and the confessional approach, lies in the shameful confidences that Rosenthal identified, it goes "beyond customary bounds of reticence or personal embarrassment".  In his 1955 poem Howl, Allen Ginsberg wrote "[To] stand before you speechless and intelligent and shaking with shame, rejected yet confessing out the soul to conform to the rhythm of thought in his naked and endless head,..."
The impetus towards more personal, more autobiographical writing, dates back at least a century and a half before Life Studies. In February 1797 Samuel Taylor Coleridge wrote in a letter to Thomas Poole: "I could inform the dullest author how he might write an interesting book—let him relate the events of his own life with honesty—not disguising the feelings that accompanied them."
In a letter to The Guardian on 20 April 1989, Ted Hughes wrote that there was a "Fantasia about Sylvia Plath".  Plath's life and poetry have been constructed in such a way as to perpetuate particular fictions about her marriage, mental illness, and "autobiographic" writing, and although this may in part be due to a mythologizing tendency among critics and biographers, it can be shown how Plath fictionalizes herself in her writing. 
Later writers such as Denise Levertov, Adrienne Rich, and Audre Lorde present personal difficulties in a socio-political context. For example, Lorde's poem, "Coal" reflects on such personal problems within a given cultural context. Levertov's "Life at War" presents something inextricably personal bound in the conflict of the age.
What defines poetry as confessional is not the subject matter, but how the issue represented is explored. Confessional poetry explores personal details about the authors' life without meekness, modesty, or discretion. Because of this, confessional poetry is a popular form of creative writing that many people enjoy not only to read but to embark upon. Another element that is specific to this poetry is self-revelation achieved through creating the poem. This passes on to the reader, and a connection is made.
Reasons behind writing confessional poetry
Poets whose writing is classified as confessional (it has been argued) use writing as an outlet for their demons. Writing and then re-reading one's work changes the cognitive processes with which one's brain processes this information—it offers perspective. Anne Sexton famously said, "Poetry led me by the hand out of madness." But she also argued against this perception in her interviews. In an interview with Patricia Marx, Sexton denies that writing “cured her”:
“I don’t think [that writing cured my mental illness] particularly. It certainly did not create mental health. It isn’t as simple as my poetry makes it, because I simplified everything to make it more dramatic. I have written poems in a mental institution, but only later, not at the beginning”.
Confessional free verse poetry seemed to have become the dominant approach in late 20th-century American poetry. Robert Bly in the preface to his 1983 translation of Antonio Machado's poetry, Times Alone, praised Machado for "his emphasis on the suffering of others rather than his own". The reaction to confessional poetry has sparked new movements such as that of the Language poets and New Formalism.
Kirsch, Adam: The Wounded Surgeon: Confession and Transformation in Six American Poets, W. W. Norton & Company, 2005.
Rose, Jacqueline, The Haunting of Sylvia Plath, Virago Press, London, 1991. ISBN 9781853813078.
Rosenthal, M. L., The Modern Poets: A Critical Introduction New York: Oxford University Press, 1960 ISBN 0195007182
Rosenthal, M. L., Our Life in Poetry: Selected Essays and Reviews, Persea Books, New York, 1991, ISBN 0892551496.
1. The Nation, September 19, 1959), reprinted in Rosenthal 1991, pages 109–112. Rosenthal somewhat reworked the review into an essay "Robert Lowell and the Poetry of Confession" in his 1960 book The Modern Poets
2. Rosenthal, 1959.
3. Thompson, John, "Two Poets," Kenyon Review 21 (1959) pages 482–490.
4. Kirsch, page 2, makes this observation in his reassessment of the historical context of Life Studies
5. Ian Hamilton, "A Biographer's Misgivings," collected in Walking Possession, Essays & Reviews 1968–1993, Addison-Wesley, 1994. ISBN 0201483971
6. The Complete Works of Samuel Taylor Coleridge, Volume III, 1854, page 601.
7. Reid, Christopher, editor, Letters of Ted Hughes (Faber & Faber, 2007 ISBN 9780571221387), pages 552–556. The letter is a response to an earlier letter to the newspaper complaining that Plath's grave was hard to find and poorly maintained; Hughes is most angered by a false assertion that Plath and he had divorced, and he attributes this to the "fantasia" generated by the academic Plath industry; the issue of the fantasia is explored in Chapter 3 of Jacqueline Rose's The Haunting of Sylvia Plath (1991)
8. Rose, page 5
9. “Interview with Patricia Marx,” Hudson Review 18, no. 4, Winter, 1965/66)
10. Bly, Robert (translator), Machado, Antonio Times Alone, Wesleyan University Press, 1983, ISBN 978-0819-56081-0, page 1.
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Version: Modified on 15 April 2008, at 01:46
Of course, this Wikipedia article is not the definitive word on confessional poetry, but merely a jumping off point for a discussion about the place of confessional poetry in the academy.
Since this is a thread on confessional poetry and its affect on poetry, I have a confession to make:
I love Sylvia Plath's poetry, for it is a mirror into her short life and offers the reader a voyeuristic view of the darker aspects of her psychological makeup; I fear her work appeals to the baser side of my personality.
However, I often wonder if the "confessional movement" has, somehow, debased "Poetry" itself.
Feel free to post your thoughts.
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