The earliest mention of Bárid in the Irish Annals is in part of a saga embedded within the Fragmentary Annals of Ireland. In this entry, dated 867, Bárid is named as a Jarl of Lochlann who, along with a Jarl Háimar was ambushed by men of Connacht. Bárid is mentioned again by a saga element within the Fragmentary Annals in 872, when he is said to have raided Moylurg and the islands of Lough Ree. This saga element also says that Bárid fostered a son of Áed Findliath, overking of the Northern Uí Néill. The sagas are usually considered of dubious historical value, but this particular element draws upon earlier written accounts, and there is much evidence for later links between the descendants of Áed Findliath and the Uí Ímair. Fosterage was used in Ireland as a means of strengthening ties between different ruling families, and it is possible Bárid may have tried to integrate himself with the Irish political elite. Bárid is mentioned by the Annals of Inisfallen in 873 which say: [|Downham] suggests this raid was undertaken as a show of strength; it occurred shortly after the death of Ímar, with Bárid probably succeeding him as King of Dublin. Cogad Gáedel re Gallaib names a son of Amlaíb, most likely Oistin, as raiding with him. It has been suggested that Bárid and his cousin Oistin ruled together as co-kings following the death of Ímar. According to the Annals of Ulster, in 875 Oistin was "deceitfully" killed by "Albann", a figure generally agreed to be Halfdan Ragnarsson, supposed son of the legendary Viking Ragnar Lodbrok. Halfdan is sometimes considered a brother of Ímar, and this conflict may have been an attempt by Halfdan to claim Dublin for his own. It seems he was not successful in pressing his claim, but he tried to take Dublin again in 877, and he fell in battle against an army of "fair foreigners" at the Battle of Strangford Lough. Cogad Gáedel re Gallaib identifies Bárid as the leader of the "fair foreigners", and as being wounded "so that he was lame ever after". The next mention of Bárid in the annals comes in 881, when the Annals of Ulster, the Annals of the Four Masters, and the Chronicon Scotorum describe his death; he was killed and burnt in Dublin shortly after raiding Duleek. The annals attribute his death to a miracle of Saint Cianán.
Family
Bárid's father is identified by the Chronicon Scotorum as Ímar, King of Dublin until his death in 873. Ímar is sometimes identified with Ivar the Boneless, son of the legendary Viking Ragnar Lodbrok. The same entry identifies him as "the head of the Northmen". The known brothers of Bárid were Sichfrith and Sitriuc. Bárid is identified as the father of Uathmarán, who bore an Irish name derived from the Irish word "uathmar", meaning ‘awesome’, perhaps in an attempt to associate with the Irish political elite. Bárid may also be identified as the father of Eloir mac Báirid, and the grandfather of the unnamed son of Uathmarán mac Bárid. This unnamed man may be identical to Sichfrith mac Uathmaráin. It is uncertain whether Bárid was the father of the unnamed son of Bárid who plundered Cill Clethi in 937. This unnamed man may be identical to Aric mac Báirith. Likewise, it is uncertain if Bárid was the father of Colla mac Báirid. Any or all of the aforementioned Aric, Colla, and the unnamed son of Bárid, could have been sons of Bárid mac Oitir, not Bárid mac Ímair.
