Heil Pens Book Chapter Detailing How Catholic Clerics Used Canon Law in Medieval Italy

A University of Arkansas at Little Rock history professor has written a book chapter outlining how Catholic clerics used canon law more than 1,000 years ago in Italy.

Dr. Michael Heil’s book chapter, “Canons, Books of Canons, and Ecclesiastical Judgments in Carolingian Italy: The Council of Mantua, 827,” was published in the book, “Networks of Bishops, Networks of Texts: Manuscripts, Legal Cultures, and Tools of Government in Carolingian Italy at the Time of Lothar I” at the end of 2022.

The chapter is a case study of the varied ways that litigants and judges used written law and the physical books that transmitted it in ecclesiastical disputes in early medieval Italy. Heil focuses on the long-running jurisdictional dispute between the patriarchs of Aquileia and Grado.

“When the Lombards came to Italy in the sixth century, the patriarch of Aquileia fled to the island of Grado,” Heil said. “Eventually, a new patriarch is elected on the mainland at the city of Aquileia, but the patriarch of Grado doesn’t give up his power. You now have two men claiming this important power within the Catholic Church. The two holders of these offices fight each other on who is the real patriarch and should have ecclesiastical authority in Northeast Italy.”

Heil’s chapter focuses on a legal case in 827, when the Council of Mantua ruled in favor of the patriarch of Aquileia.

“We have a record of the arguments made by the patriarch of Aquileia,” Heil said. “The patriarch of Grado wasn’t present. It was clear to him that the deck was stacked, and he wasn’t going to win. The patriarch of Aquileia makes arguments that hinge on the norms of canon law. His audience would have understood that. Even when people are not citing chapter and verse of written law, the written law is also in the background of legal arguments.”

While the Council of Mantua decided that the patriarch of Aquileia was the legitimate patriarch of the land, Heil said the legal dispute would continue on for centuries.

“Although it seems definitive, it doesn’t actually change much of anything,” Heil said. “The patriarch of Grado would later appeal the ruling, and he seems to have argued that the canon-law argument made against him at Mantua actually applied to the patriarch of Aquileia. In response the patriarch of Aquileia had to develop new lines of argument. The patriarch of Grado stays around for a long time.”

The book brings together research that was presented during a 2021 virtual conference [on the ways that bishops used law and other texts in ninth-century Italy hosted by the University of Padua. The conference and the book are part of a multiyear Italian project, “Ruling in hard times. Patterns of power and practices of government in the making of Carolingian Italy.”

Heil also completed some of the research for the chapter during the  2019-2020 academic year, when he served as the Mellon Junior Faculty Fellow and visiting assistant professor at the University of Notre Dame’s Medieval Institute. This fellowship, awarded each year to one medievalist across fields, allows the recipient to pursue research in Notre Dame’s unparalleled library holdings in medieval studies. Heil was able to research in the Medieval Institute’s Biblioteca Ambrosiana Collection, which features microfilms of more than 10,000 manuscripts from the Ambrosiana Library in Milan along with a supporting print collection.