This probably isnt common knowledge, but in the third crusade Ricahard I and Salah al-Din actually considered as a peace arrangement to marry Richards sister Joanna of Sicily and Saladins brother Al-Adil to each other and allow them to rule Jerusalam. I've been writing a book about this with a few changes, and i wanted some outside opinions. I changed several things including keeping Raymond III alive long enough to see the third crusade, and marrying Joan to one of Saladins sons instead of his brother. Further, while it is was looked upon badly to marry out of religion the Koran has never spoken against it and even allows it to Christians or Judiasts as long as the man is Muslim. Ive done a large, large amount of research and plenty of sources supporting the idea that if it had been pushed just a bit more that a marriage could have been possible.