sentences:  The latter's principal adherents on the western seaboard of Scotland were Clann Dubhghaill, regional rivals of Clann Domhnaill.Although there is much uncertainty concerning the Clann Domhnaill chiefship at this period in history, at some point after Alasdair Óg's apparent death at the hands of Clann Dubhghaill in 1299, Aonghus Óg seems to have taken up the chiefship as Lord of Islay.Pressure from Clann Domhnaill and other supporters of the English Crown evidently compelled Clann Dubhghaill into coming onside with the English in the first years of the fourteenth century.