It happened to me as well in my Brutii Campaign. The Julii were getting their butts kicked by the gauls until the Julii only had Ariminum, and the islands of Caralis and Palma. I thought for a second, what if the Gauls grew too much in power and then took Rome and Capua from the Scipii? Next on the road was me!
So what I did was to send a couple of spies and assassins to assist the Julii in their return to conquer their cities back. I killed Barbarian Generals and destroyed their buildings causing chaos in their cities. The Julii managed to take back their cities and they expanded West.
Now I'm in the middle of the Civil War, and my worst problem is the Julii as they have a lot of troops standing in their borders, as well as in their towns.
I somehow regreat what I did when I helped them. But I'm a Roman, they were my brothers, and I did my duty as a true Roman!
Even though I helped them, now that they are my enemies and that I'm going to take their cities I can thank them to impose good Roman culture to the savage Barbarian Towns.
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