 Hostages were taken from Sigtrygg by Flaithbertach Ua Néill , King of Cenél nEógain and the Uí Néill , and Donnchad mac Briain of Munster in 1025 and 1026 respectively , in support of their bids for the high kingship . These hostages brought no security , and Dublin was raided in 1026 by Niall mac Eocada of the Ulaid in revenge for the naval attack of 1022 . Sigtrygg formed a new alliance with the men of Brega . In 1027 , Sigtrygg 's son Olaf joined Donnchad of Brega in a raid on Staholmock , County Meath . Sigtrygg and Donnchad 's army was defeated by the men of Meath under their king , Roen Ua Mael Sechlainn . Sigtrygg rallied to the fight again at Lickblaw where Donnchad and Roen were slain . 
