In the eleventh century the population growth and the recovery of craft and commercial activities resulted in the revival of the city and the flourishing of the local culture, a slow and gradual process that developed in a non-uniform way in the central and northern regions of Italy and some areas of Southern France and Germany. The city became a magnet for people from different social backgrounds: urbanized farmers and minor landowners living together with artisans, merchants, judges and notaries, the first nucleus of the emerging bourgeoisie.
With the establishment of the municipality, towns become sort of city-states: claiming their autonomy from feudal bonds and imperial authority and adopted their own regulations, put under their direct control the surrounding countryside. The economic and demographic recovery, and the increase in commercial traffic made social and economic relations more complex: the simple and lean customary laws, which in previous centuries had regulated civil relations, were no longer sufficient to interpret a reality that had become extremely composite.
It is in this context that the commentators of the Bolognese school of the XII century, in opposition to the barbaric laws then in use, rediscovered Roman law and reinterpreted the forgotten texts of the Corpus Iuris Civilis - the monumental compilation work promoted by Justinian in the sixth century to tidy up the legal system of the empire - and engaged in a subtle work of interpretatio, revising and adapting the old laws to new circumstances and presenting them as current regulations, expression of imperial authority, thus making the Corpus Iuris Civilis the very basis of the common European law.
The glosses, the more or less complex explanations relating to the grammatical structure or interpretation of the text, were affixed by magister during the lectura to students in the margins or between the lines of the text. Even after the invention of print, books still retain the same structure of the ancient manuscripts: the centre of the page was the litera, and all around stood the glosses. The passionate work of Irnerius and his students made a fundamental contribution to the development of European civilization: the glosses in fact marked the beginnings of a European law that was written, systematic, understandable and rational.
