Peacemaking and the restraint of violence in high medieval Europe : [contributions from the international conference 'Peacemaking and the restraint of violence in the Middle Ages (1100-1300)' held at the Norwegian Academy of Science and Letters in Oslo on 22 and 23 February 2018] / edited by Simon Lebouteiller and Louisa Taylor / London : Routledge, Taylor & Francis group , 2024