Have you had that moment where you were a imperial dynasty that you created with your own hands on Ironman, only for you to end up seeing the empire disappear not through conquest but through a succession occurrence, which sees you the Chief of the Canaries? I had a wonderful game as the Haestein Dynasty, having began with a prepared invasion of Wessex, followed by subjecting the Norse Yorkshire into my dynasty so that I could become King of England. The 5th char, Linda, managed to become the first Empress of Britannia. Marriage allowed my char to inherit the Norse religious head, who was Denmark, then over the time the empire went from Finland to north Germany to France to Portugal and Rome. The Kingdom of Italy was among the strongest Catholic power in the end. Norway and Sweden stood with the Norse kingdom of Rus. The Tengi faith reformed. Andalusia was under the Shia Caliphate.
The Shia Caliphate declared a Jihad on Portugel while I was defending against the Sunni Jihad on Africa. I had gained Portugel from the Shia Caliphate by a earlier Great Holy War. The Jihad went back and forth: the Caliphate and his friends occupied, I managed to win epic battles. Our numbers reduced and land once again reoccupied, I regrouped forces... then in one epic battle the Emperor was slain... along with the Empire.
I think I was a fault in this; I had earlier managed to get Primogeniture for Britannia but not for the Kingdom of England which I still held on to, which had a succession issue with my second heir likely to get both Wessex and England. That said there was no hint that the Empire would die after that...
On the plus side the map would make good for a EU4 game, even if the Kingdom of England now is based around London... still Norse Portugal stands.