Well, my advice is to create dukedoms and counties with different families, of same culture of your character if possible. This will improve the "genetic pool" of your culture, lowering cases of marriages of people from the same House.
That bird has flown I'm afraid. It's been quite a while since I played. Mistakes have been made, but that can add to the fun and drama. CK is more RPG to me than strategy game. And other excuses for forgetting to preserve some other Irish dynasties, umm, yeah.
I decided to take a chance. There are a few Ui Morda counties/duchies from my reconquista of the British Isles (early fallers to the Fatmids. That was scary...). So I'm taking a chance and going elective and trying to rig it so a healthier Ui Morda branch is on the throne. I'm hoping to hang on until the end and convert to EUIII. Hopefully there is still a health Ui Morda branch out there that still counts as Irish, although Scots, Welsh or Saxon would do given my teritories.
Wish me luck. (its 1240's now, Byzantium is strong in the east. In the west, the Spanish kingdoms are, as usual, gone, but so is France! and Sweden. Should make for an interesting next 2 centuries).
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NOOOOOOOOOOOOOOOOOOOOOOOOOOOooooooooooooooooooooooooooooooooooooooooooooooooooooooooo
So close. King dies of plague. Favoured candidate is elected. As a child. Manages to not die of the Plague. Grows up, marries a nice girl, just 2 years to go until I can change inheritance laws and BAM! Assasinated. Who ends up on the throne. Yup, the inbred misfits.
Damn you game, why must you make me fight and struggle for every damned little thing*shakes fist at sky*
Man, I forgot how much fun this game is.