 In 1075 , Toirdelbach drove Gofraid from the kingship and Ireland itself . There is uncertainty concerning the circumstances of Gofraid 's expulsion , and of Domnall 's accession . On one hand , it is possible that Gofraid was involved in lending assistance to Anglo @-@ Danish resistance against the Norman regime in the recently conquered Kingdom of England . If correct , Gofraid would appear to have been at odds with Toirdelbach , a monarch who appears to have cultivated close links with the Norman regime . Domnall , therefore , may have had Toirdelbach 's consent to rule in Dublin as Gofraid 's replacement . In fact , Toirdelbach 's placement of Domnall in Dublin , and his allowance of the latter 's aforesaid cousin in Leinster , may have been a way in which the Uí Briain exploited the fractured Uí Chennselaig . Certainly , Domnall 's cooperation would have been a valuable asset to Toirdelbach , considering the prominence of his father amongst the Dubliners , and the likelihood that Domnall himself may have lived most of his life there . On the other hand , it is possible that Gofraid was driven from the kingship because he had aligned himself with the <unk> against the Uí Briain . If such a sequence of events is correct it could mean that , even though Gofraid was unable continue on with the revolt , it was his Uí Chennselaig <unk> who succeeded in securing Dublin from the Uí Briain . 
