Complex sentence: Maurice O'Leochain is listed as bishop of Kilmadaugh for the period 1254-1283 indicating the prominant members of the sept were driven across the Shannon by the Anglo-Norman Invasion as were Mac Maolains who then surface in Roscommon as erenaghs and clerics.
Split into simpler sentences: Maurice O'Leochain is listed as bishop of Kilmadaugh for the period 1254-1283. Prominant members of this sept were driven across the Shannon by the Anglo-Norman Invasion as were Mac Maolains who then surface in Roscommon as erenaghs and clerics.