Lion heart - Justin Cartwright

Richard Cathar was named after his father's hero, Richard the Lionheart. Richard remembers his recently-deceased father, Alaric, as a delusional hippy, who saw himself as an intellectual and historian. Following in his father's footsteps, Richard travels to Jerusalem where he falls deeply in love with Noor, a beautiful but mysterious Canadian-Arab journalist. When Noor is kidnapped on assignment in Cairo and the facts of her capture emerge, Richard stumbles upon an important document, one that could rewrite not just the history of the Crusades, but his father's and his own as well.