This is a broad history of the western European legal tradition. From the modern age the author looks back to a time when Europe had a common law that transcended national and legal boundaries. This common law, which Bellomo calls the ""ius commune"", had developed in the 12th century from the fusion of Roman, canon and feudal law. Existing within the framework of the ""ius commune"" were the local laws or ""iura propria"" - the myriad laws of everyday life, the laws particular to the various kingdoms, principalities, cities, guilds and secular and ecclesiastical corporations. Bellomo illustrates how for centuries the ""ius commune"" permeated every aspect of the ""iura propria"", marking European law indelibly with its stamp. Because the ""iura propria"" emerged from the unifying norms and principles of the ""ius commune"", one can not properly understand local European systems of law without first understanding the ""ius commune"" and its influence on the legal concepts, institutions, procedures, documents, and doctrines of the ""iura propria"". Linking his history to modern day concerns, Bellomo argues that the codification that occurred in European countries during the 18th and 19th centuries has introduced ambiguity, rigidity and uncertainty into legal systems. A new common law for the whole of Europe, he asserts, would provide a much better vehicle for legal change and development in a time when the economic barriers between European nations are crumbling. Bellomo then describes the beginnings of the ""ius commune"" in the schools of the 12th century, discusses the development of Italian, French and German ""iura propria"", and incorporates into the text sketches of the great jurists who gave common law its intellectual vigour. He concludes with an account of the humanist jurists of the 15th, 16th and early 17th centuries.