Mary Devenport O'Neill (August 3, 1879 - 1967) was an Irish poet and dramatist and a friend and colleague of W. B. Yeats, George Russell,and Austin Clarke.
Devenport was born in Loughrea, Co. Galway, Ireland. She was a pupil of the Dominican Convent in Eccles Street, Dublin where her family moved after the death of her father, an R.I.C. sub-constable in Loughrea. From 1889-1902 she studied teaching at the Metropolitan College of Art now called National College of Art in Dublin. She published three verse plays,Bluebeard (1933),Cain(1945),and Out of The Darkness (1947). Her final play War, The Monster was performed by the Abbey Eperimental Theatre Company in 1949 but was not published. When she was fifty, she published a collection of poetry Prometheus and Other Poems (London: Jonathan Cape 1929) which comprises thirty-three lyric poems, four "dream poems," one long poem, and a verse-play. She published regularly in The Dublin Magazine and contributed reviews to The Bell and The Irish Times. Two of her plays were performed by Austin Clarke's, Lyric Theatre Company and Devenport engaged in lengthy correspondence with him from 1929-1948 concerning the production of her work and combining choreography with verse for these productions. Bluebeard, a ballet based on her play, was choreographed by Ninette de Valois as one of the final productions of the Abbey school of ballet. Her work shows the influence of imagism and displays a modernist cynicism towards Revival themes. She refuses heroic imagery to adopt a feminist approach to masculine narratives. Her collection "Prometheus and Other Poems" was the first collection of poetry published by an Irish Poet, besides W.B.Yeats, which could be considered modernist. She is one of a small number of known early 20th century Irish modernist women poets.
Her regular Thursday salon was attended by W.B. Yeats, AE, Austin Clarke, Frank O'Connor and other prominent Irish writers and artists. She had a reputation as a psychic and served as consultant to Yeats while he was working on his book A Vision.
She married in 1908 and her husband, Joseph O’Neill was an Author and Permanent Secretary of the Department of Education. W.B. Yeats, in his role as a member of Seanad Éireann, learned about the Irish education system from the O'Neills.