This book presents a novel framework for studying historical legalisation using quantitative methods, with 10 fully-preserved laws from medieval Sweden, written between c. 1225 and 1350, serving as a case study. By applying a systematic classification scheme to each legal provision, it is possible to investigate the major differences and similarities in structure and content between the 10 laws. This, in turn, allows for the re-assessment of many long-standing problems in Swedish and European medieval legal history that have been challenging to address with traditional methods based on text analyses. Over the course of the thirteenth and fourteenth centuries, major changes in the proportion of legal provisions devoted to different fields of law, and to prescribed consequences, are found. The book shows how the proportions of civil law and public law expanded at the expense of criminal law. Furthermore, a clear transition from casuistic to more abstract law provisions can also be witnessed.