The Irish tribes have banded together under one Warlord, perhaps this time history will be on their side. A quasi-historical Faction Replacement Mod this mod replaces Numidia and comes in two forms, one intended for the Player to control and another to be an AI opponent (the Player variant was too difficult for the AI to use).
This is the Player Version of the Faction Mod. Extract the file to your root RTW folder, create a RTW Shortcut and add -mod:ireland to the end of the Target in order to run the mod. [E.g. "C:\SteamLibrary\steamapps\common\Rome Total War Gold\RomeTW.exe" -mod:ireland]