Law and War in Late Medieval Italy: The Jus Commune on War and Its Application in Florence, c. 1150-1450
By Ryan Greenwood
PhD Dissertation, University of Toronto, 2011
Abstract: This study, on law and war in late medieval Italy, has two primary aims. One is to review the legal tradition on war as it developed in the medieval jus commune, or common law, from approximately 1150-1300, and then to consider how that tradition evolved from roughly 1300-1450. In general the latter period still represents a lacuna in scholarship on the legal theory of war, and can be addressed as a distinct period because the fourteenth century was a time when theory moved in important new directions. It will be suggested in turn that those new directions were related to changing politics and institutions in Italy. The second aim continues and reflects the first, as it seeks to better understand how legal arguments about war and peace were employed in practice, using Florence as an example. The study finds that these legal arguments found their most important role in diplomacy. Florentine diplomatic records, as well as legal opinions (or consilia) on inter-city disputes, will help to examine the complex nature of that role. In general it will be seen that the law, including the jus commune, was a strategic tool and an important regulatory mechanism for relations between political actors in late medieval Italy, though one that also had significant limitations.
The first chapter introduces the material and themes. The second treats the just war tradition and laws on war through 1300. The third chapter examines legal theory on war, particularly in Roman law, from roughly 1300 to the early fifteenth century. The fourth explores how just war arguments were deployed in Florentine political discourse between 1230 and 1430. The fifth chapter examines a range of legal issues related to war, as found in diplomatic instructions and consilia which played a role in Florentine wartime diplomacy from 1392-1402. The sixth chapter is the conclusion.