A lot has been written on medieval Christian holy war (often called "the Crusades") - some of it good and some bad. Here's a short reading list to start your exploration of the topic.

Luyster’s research findings underpin the exhibition “Bringing the Holy Land Home: The Crusades, Chertsey Abbey, and the Reconstruction of a Medieval Masterpiece,” which runs Jan. 26 to April ...

Ward’s majestic book reminds us that there is little new under the sun, ... A Global History of the End of Britain, by Stuart Ward, Cambridge University Press, 550pp, £30.