Custom was fundamental to mediaeval legal practice. Whether in a property dispute or a trial for murder, the aggrieved and accused would go to lay court where cases were resolved according to custom. What custom meant, however, went through a radical shift in the mediaeval period. Between the twelfth and thirteenth centuries, custom went from being a largely oral and performed practice to one that was also conceptualised in writing. In Vernacular Law: Writing and the Reinvention of Customary Law in Medieval France (Cambridge University Press, 2022), Dr. Ada Maria Kuskowski uses French lawbooks known as coutumiers to trace the repercussions this transformation – in the form of custom from unwritten to written and in the language of law from elite Latin to common vernacular – had on the cultural world of law. Vernacular Law offers a new understanding of the formation of a new field of knowledge: authors combined ideas, experience and critical thought to write lawbooks that made disparate customs into the field known as customary law. This interview was conducted by Dr. Miranda Melcher whose forthcoming book focuses on post-conflict military integration, understanding treaty negotiation and implementation in civil war contexts, with qualitative analysis of the Angolan and Mozambican civil wars. Learn more about your ad choices. Visit megaphone.fm/adchoices Support our show by becoming a premium member! https://newbooksnetwork.supportingcast.fm/law