Quote Originally Posted by Uesugi Kenshin
Does the AI recruit them a lot?
I'm not to sure about Germanic and nomadic factions since I've chocked the Rhine and Danube with forts to keep barbarian factions at bay, but I've noticed that the Celts tend to build up armies just on the border of Britannia. A full stack Celtic army almost always has 1 - 2 units of berserkers (Hounds of Culan).