There is a genre of Irish language songs in which a spoken story is allied with the sung piece. Some of these old song-stories have in the past century inspired plays, story books, longer books. Dúbhglas de hIde based his play "Casadh an tSugáin" on the song of that name (known in English as Twisting the Hayrope, but I havent heard or read any English language lyrics), Cliodhna Cussen wrote a children's book of the story of "An Bhean úd Thall" (Irish version of An Bhean Eudach), and there's a couple of books based on the story of Úna Bhán. Lyrics and info about those 3 songs are already on Mudcat.

I see via internet that there is a book by Patrick Devanney titled "Una Bhan: Flaxen Haired Rebel" http://www.independent.ie/regionals/sligochampion/news/former-summerhill-students-novel-tells-na-bhn-story-27563979.html "

Many will have heard the legendary tale of Úna's ill-fated love affair with Tomás Láidir Costello: her father refused to allow them to marry and Úna died of a broken heart; Tomás used to swim to Trinity Island in Lough Key to keep vigil at her grave, resulting in his death from pneumonia; he was buried beside Úna and two trees grew over their graves, which intertwined to form a lovers' knot.

"Using a novelist's license in his latest book, 'Úna Bhán, Flaxen-Haired Rebel', Patrick Devaney paints a very different picture of Úna. Far from being a "garden rose" or a "gold candle on the queen's table", as portrayed by her poet-lover Costello, Devaney depicts Úna as a courageous but troubled young woman who demands to be treated as an equal in the maledominated world of the 17th Century. She becomes a rebel committed to driving the foreigners out of Ireland"