sentences:  Clann Dubhghaill authority along the western seaboard was seriously threatened by about 1296, when Alasdair Óg was acting as Edward I's royal representative in the region.Certainly, Alasdair Óg appealed to the English king regarding Alasdair Mac Dubhghaill's ravaging of Clann Domhnaill territories in 1297, and may well be identical to the like-named Clann Domhnaill dynast who was recorded slain against Alasdair Mac Dubhghaill two years later.If this identification is indeed correct, this could have been the point when Aonghus Óg succeeded Alasdair Óg as chief.