In the year 1200 John of England took Isabella, daughter of Aymer Taillifer, Count of Angoulême, as his wife. However Isabella had already been promised to Hugh X of Lusignan by her father. (She had only been 13 at the time and when John died she'd marry Hugh anyways) This marriage lead to Hugh complaining to Phillip II, King of France, who then went to seize the Norman king's land in France.
What happens if John chooses to leave Isabella alone?
What happens if John chooses to leave Isabella alone?