You can do the mod yourself, its easy (even I managed it).Originally Posted by Excalibur Bane
Find your Rome:Total War folder and open it.
Select Data>World>Maps>Campaign>Imperial_Campaign
Find the file descr_stat, make a back up of it and put it somewhere where you can find it (I have a backup folder in my TW directory). Now open the original file in Notepad.
You will notice that there are a list of factions split up into Playable, Unlockable and Nonplayable. Simply cut and paste the Non-Playable factions you want into the Unlockable section.
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