I just checked and while I don't have a save from right when it happened, I have one from later in the same game so you can at least see how the cities are laid out. Here's a link to that:
https://dl.dropbox.com/u/108352382/mlm.EleSav
At the time that it happened, I owned Tan-Ta-Kreet, Gildenshard, and Fargan's Keep. Tarth had Hope, and I'd signed a non aggression treaty with her. Magnar had Curgeon's Hold, Imperium, Rilkaz, and another settlement and some outposts southwest of Curgeon's Hold that I had already razed. I had not previously owned any of Magnar's settlements, except for that one that I'd already razed. My sovereign had some Shields of Gilden with him, and maybe some warriors too. He didn't have a champion with him. I moved him past Curgeon's Hold and Imperium without attacking them since they were too heavily defended. He ran out of movement on that road between Rilkaz and Imperium, one square from Rilkaz. I was going to attack Rilkaz the following turn since it wasn't well defended, but then Magnar came up the road behind my sovereign and attacked. I think he had some spearmen and slave militia with him. I played out the fight manually, but he blew through my guys with that big axe of his and I lost. That's when my sovereign got dumped in Rilkaz, and I controlled that fight manually, which was against a couple militia. When I won, I got Rilkaz and my sovereign was immobilized in it. Magnar took it back a turn or two later, and that time my sovereign retreated to Tan-Ta-Kreet.
I think that's all the info you were asking for, let me know if anything else would be helpful.
