ABSTRACT
The greatest book on canon law written in the western Middle Ages — some would argue that it is the greatest book on any kind of law written in the western Middle Ages — is the Concordance of Discordant Canons. It was composed around 1140, perhaps a bit earlier, by a man named Gratian, of whom we know virtually nothing, except that he almost certainly was active in Bologna. He is thought to have founded what was to become the first faculty of canon law in western Europe, and the Concordance, also known as the Decreta, seems to have been designed as a teaching book.1
