 Later chroniclers record that Ireland enjoyed a "Forty Years' Rest" from foreign invaders between 876 and 916.Hálfdan was slain in a battle with the Findgaill in Loch Cuan (Strangford Lough) in 877.In the relevant entry in the "Annals of Ulster" he is described as the leader of the Dubgenti; In "Cogad Gaedel re Gallaib" Barith is named as the leader of the Findgenti; this would seem to support the theory that Hálfdan's brother Ingware was not the same man as Ímar the Norse king of Dublin, the former being of the Dubgenti and the latter of the Findgenti.