Common law
The common lawso named because it was "common" to all the king's courts across Englandoriginated in the practices of the courts of the English kings in the centuries following the Norman Conquest in 1066. Prior to the Norman Conquest, much of England's legal business took place in the local folk courts of its various shires and hundreds. A variety of other individual courts also existed across the land: urban boroughs and merchant fairs held their own courts, as did the universities of Oxford and Cambridge, and large landholders also held their own manorial and seigniorial courts as needed. Additionally, the Catholic Church operated its own court system that adjudicated issues of canon law.
Legal history
After much of the West was consolidated under Charlemagne, law became centralized so as to strengthen the royal court system, and consequently case law, and abolished folk-right. However, once Charlemagne's kingdom definitively splintered, Europe became feudalistic, and law was generally not governed above the county, municipal or lordship level, thereby creating a highly decentralized legal culture that favored the development of customary law founded on localized case law. However, in the 11th century, crusaders, having pillaged the Byzantine Empire, returned with Byzantine legal texts including the Justinian Code, and scholars at the University of Bologna were the first to use them to interpret their own customary laws. Medieval European legal scholars began researching the Roman law and using its concepts and prepared the way for the partial resurrection of Roman law as the modern civil law in a large part of the world. There was, however, a great deal of resistance so that civil law rivaled customary law for much of the late Middle Ages.