The facts that emerge from any review of the battle are that the Three Collas were victorious in the battle(s) of Achadh Leith-dheirg in "Fearn-mhagh" and that they drove the Ulaid beyond the Glen Righe. The Three Collas took from the Ulaid the land west of Glen Righe and Loch nEathach (Lough Neagh).
In the context of the conflict, it is evident that the Three Collas achieved a decisive victory in their battles against the Ulaid, particularly in Achadh Leith-dheirg in "Fearn-mhagh", and they were able to drive the Ulaid beyond the Glen Righe. As a result, the Three Collas gained control over the land west of Glen Righe and Loch nEathach (Lough Neagh).