The ecclesiastical jurisdiction within Rǫgnvaldr's realm was the far-flung Diocese of the Isles. Like the Kingdom of the Isles itself, the origins of the diocese may well lie with the Uí Ímair "imperium". In the mid twelfth century, during the reign of Rǫgnvaldr's father, the diocese came to be incorporated into the newly established Norwegian Archdiocese of Niðaróss. In effect, the political reality of the Diocese of the Isles—its territorial borders and nominal subjection to Norway—appears to have mirrored that of the Kingdom of the Isles. Before the close of the twelfth century, however, evidence of a new ecclesiastical jurisdiction—the Diocese of Argyll—begins to emerge during ongoing contentions between the Meic Somairle and the Crovan dynasty.