" As Petrus Alfonsi, the converted physician authored a book called the Disciplina Clericalis, which was essentially a collection of Arabic tales translated into Latin. These tales introduced a mode of Oriental storytelling and wisdom literature into Christendom that would become extremely popular. In the section called “The Mule and the Fox,” concerning the true nature of nobility, Alfonsi listed seven accomplishments expected of a knight. “The skills that one must be acquainted with are as follows: Riding, swimming, archery, boxing, hawking, chess, and verse writing.”6 So, by the beginning of the twelfth century, chess had become a mandatory skill for Spain’s elite warriors. "

― Marilyn Yalom , Birth of the Chess Queen: A History