CK2 and Mount and Blade:

Basically you start from nothing, usurp the king who only has an army of 200 peasants while you rock around with an army of 400 full plate knights. And then you basically play CK2 until its time to lead an army where you do it mount and blade style. Oh, also marriage requires you to go through an obnoxious courting ritual which may or may not end up in a dual with the dad.

Not going to lie, it sounds pretty cool.