 Donnchadh Mór, who was son of Murchad Óc, and grandson of Murchad Mear, was the first Suibhne na d'Tuath.Donnchadh's father and grandfather had conquered large tracts of land in Tír Conaill in about 1314.In 1359 when Ó Conchobhair defeated Séan Ó Domhnaill, Donnchadh Mór's son, Eoghan Connachtach, was held captive by the son of Ó Conchobhair Shligigh.