Built in 1788 for Colonel William Persse on his return from the American War of Independence, Mount Vernon was named to celebrate his friendship with George Washington. The three remaining Monterey Cypress trees in the walled garden are thought to have been a gift from the President.

During the nineteenth century, Mount Vernon was the summer home of Lady Augusta Gregory of Coole, an accomplished playwright and folklorist, and a pivotal figure in the Irish Cultural Renaissance. It was her collaboration with W.B.Yeats and Edward Martyn that created the Abbey Theatre in Dublin in 1904. Lady Gregory entertained many of the luminaries of the Irish Literary Revival at Mount Vernon including W.B.Yeats, AE (George Russell), O’Casey, Synge and George Bernard Shaw. W.B.Yeats is said to have written The Player Queen and The Dreaming of the Bones while staying here.

In 1907, Lady Gregory gave the house to her son Robert Gregory as a wedding present and it was from here that he produced many of his fine paintings of the Burren landscape. He later joined the Royal Flying Corps and was shot down by 'friendly fire' in 1918, an event commemorated by W.B.Yeats in his famous poem, An Irish Airman Foresees his Death. A feature from this period are the unusual fireplaces designed and built by his close friend the pre-Raphaelite painter Augustus John.