Decided to give up on Loins (for now!), and play as a Warrior. I got lucky with the starting location.
Everything was going smoothly, which once again convinced me that it's easier to play as a Warrior under these conditions. Ivor came to my castle, but he didn't have many troops, so he retreated.
I followed him. On day 134, I attacked his main city. The opponent surrendered.
Thanks to the opponent for the game!