The aisling is an Irish dream poem in which Ireland appears to the poet personified as a woman.

From A Poet’s Glossary

The following additional definition of the term aisling is reprinted from A Poet's Glossary by Edward Hirsch.

Irish for “dream.” The aisling (pronounced “ashling”) is a vision or dream poem, which developed in Gaelic poetry in Munster during the late seventeenth and eighteenth centuries. It has its origins in the Old French reverdie, which celebrates the arrival of spring, often in the form of a beautiful woman. The aislingí present and personify Ireland in the form of a woman, who can be young or old, haggard or beautiful, lamenting her woes. The woman is usually referred to as a spéir-bhean (sky-woman). Aodhagán Ó Raithille inaugurated the tradition of the political aisling with his eighteenth-century poem “Mac an Cheannuidhe” (“The Merchant’s Son”), which closes on a note of total despair. Throughout the eighteenth century, the form took on a strong political ethos, expressing a passion for Irish deliverance.

In The Hidden Ireland (1924), Daniel Corkery calls the aisling an “intimate expression of the hidden life of the people among whom it flourished.” The aisling provides the legacy for such iconic female figures as Cathleen Ni Houlihan, the Shan Van Vocht, and Dark Rosaleen. The subgenre still reverberates, though reflexively. Seamus Heaney has several aislings, including “Aisling” (1974), “An Aisling in the Burren” (1984), and “The Disappearing Island” (1987), which he recognizes as “a form of aisling, a vision poem about Ireland, even though it is an aisling inflected with irony: ‘All I believe that happened there was vision.’” In Paul Muldoon’s mock-vision poem, “Aisling” (1983), written in light of the 1981 prison hunger strike in Northern Ireland, the maternal figure of Ireland is recast as Anorexia. In A Kind of Scar (1989), Eavan Boland calls the aisling tradition “that old potent blurring of feminine and national.”

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