Slitherine

I am playing a game as the Hiberni. I have all of Ireland and have also conquered a few independent regions on the west coast of Britain as well. At some point, the Picts declared war on me and attacked. I won every battle against them and had conquered a few of their regions. They were in the process of besieging one of my regions but it was holding out and I was moving a large army to put a stop to the siege when they offered peace.

The only clause of the treaty listed was an offer of 500 gold to end the war. I thought this was appropriate since I has been beating them and I had no desire to continue expanding at this point so I accepted the treaty. However, when the treaty went into effect, all the regions that I had conquered reverted back to control by the Picts even though I still had armies in the regions. I would not have accepted the treaty if I knew I would lose the regions. Is returning regions normal? Did I need to click somewhere else to see the 'fine details' of returning conquered regions as part of the treaty?

If you don't demand their regions in the peace deal you will revert to them.