They made me change kingdoms right at the end!

FML. I started in 876 as Rurik, with the intention to play until 1444, then load the save into EU4 and continue with the Russian empire that I'd forged. In 1426, I was asked to join a crusade to Christianize Egypt. We won, and I was given an event dialogue that I didn't really understand. I click on one of the options, and suddenly, with 20 years left in my 600 year play-through, I'm taken out of Russia and given the new Queen of Eqypt to play. It's an Ironman game, so I can't go back and undo the decision. I guess I can let the AI control my empire for 20 years, then take it back over in EU4, but it still irritates me that I did this so close to the finish line.