Because he was the previous lord and duke of the region, and only lost it because the region starved when you cut Dwilight's food supply?
A ruler can make himself duke of an existing duchy. A ruler can create a new duchy. Why can a ruler not combine these two?
his argument is missing something which is a duke can appoint lords, so why can't a duke agree to allowing the ruler become lord of one of his regions with the ruler making a duchy with him instantly duke if both want/agree to it.
