Mad King Sweeney

Buile Shuibhne or Buile Suibhne ([ˈbˠilʲə ˈhivʲnʲə], The Madness of Suibhne or Suibhne's Frenzy) is an old Irish tale about the Suibhne mac Colmain, king of the Dál nAraidi, driven insane by St. Ronan's curse. The insanity makes Suibhne leave the Battle of Mag Rath, enter a life of wandering (which earns him the nickname Suibne Geilt or "Mad Sweeney"), until he dies under the refuge of St. Moling.

The tale is the final installment of a three-text cycle in medieval Irish literature, continuing on from Fled Dúin na nGéd (The Feast of Dun na nGéd) and Cath Maige Rátha (The Battle of Mag Rath).

Suibhne's name appears as early as the ninth century in a law tract (Book of Aicill), but Buile Suibhne did not take its current form until the twelfth century. Ó Béarra (https://vanhamel.nl/codecs/%C3%93_B%C3%A9arra_2014a) includes a detailed analysis of the language and date of the text.

The identity of Suibhne is a very convoluted matter as several texts mention different Suibhnes in regards with the Battle of Mag Rath. Buile Suibhne specifies Suibhne as the son of Colman Cuar and as the pagan king of Dál nAraidi in Ulster in Ireland (in particular in the areas of present-day county Down and county Antrim). This particular Suibhne son of Colman's name can also be found in the Annals of Tigernach and the Book of Lismore. The Annals of Tigernach state Suibhne, son of Colman, died in the Battle of Mag Rath, making Buile seem a fanciful imagining of dead warrior. Historical records of Dál nAraidi do exist. It was a historical kingdom inhabited by a Pictish people. However the king lists of Dál nAraidi in the Book of Leinster fail to mention any Suibhne son of Colman Cuar as king, and identifies Congal Claen as king of Dál nAraidi during this time. James G. O’Keeffe has hypothesized a possible scenario where Suibhne might have been elected by the Pictish people to act as regent in the midst of King Congal's exile.

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Wikipedia