The oddity of Castilian fashions
In Chapter 5 of the book there is a mention of the rather odd fashions which prevailed in Castile, where the Islamic influence for repeated patterns coincided with a taste for heraldic design - leading to clothes covered with repeated iterations of a family or personal badge. The effect is a little hard to picture, but here is a lovely example: Eleanor's brilliant brother Alfonso X "The Learned" wearing a robe composed not just of iterations of the Castilian and Leonese arms (castles and lions, obviously!) but red and gold castles fighting with white and black lions. Gaudy does not begin to describe it, does it? No wonder the Londoners thought the Castilian enoys looked rather odd - note, too the terrible hat to Alfonso's right. You can see a very similar approach in an actual fragment of one of Ferdinand III's robes at page 110 of "al Andalus: the Art of Islamic Spain".
It would seem that Eleanor herself was never entirely cured of this taste; for not only do the Eleanor Crosses feature her arms over, and over and over again (see the illustrations in the book), but if you look carefully at the pillow on which her head rests on her tomb there is the identical pattern to that worn by Alfonso and Ferdinand - hundreds and hundres of castles and lions. You can take the princess out of Castile, but you can't take Castile out of the Queen.