Quote Originally Posted by SZbNAhL View Post
So it turns out my understanding of inheritance laws was somewhat inaccurate. I'm the shiny new King of Scotland and decided that my first order of business should be retaking the Duchy of Lothian (it's a sorry state of affairs when Edinburgh's English). I invited the heir to my court, gave him a county and then arranged a fun hunting trip for the young Duke as a sort of "getting to know you" affair. Always a good idea to maintain foreign relations and all that.

Following the tragic hunting accident I expected my vassal to inherit the Duchy and thus give me indirect control. What actually happened was that my vassal inherited the Duchy and gave the King of England direct control over the County of Ross.

So did I need to give him an equivalent title (i.e. a Duchy) or is there something else I'm missing?
Yeah, equivalent or higher. Also the Laws of England might play a part as well, if they have no external inheritance.