This collection includes more than 90 manuscript books about law dating from before 1600 AD and representing a variety of languages and jurisdictions. The dates of their production range from the early 13th century to the end of the 16th century, and the texts contained in them represent more than fifteen hundred years of legal tradition from classical antiquity through the Middle Ages. They pertain to jurisdictions covering the Mediterranean basin, Western Europe, and the British Isles, and they cover legal systems including Roman law, canon law, feudal law, and the customary law of the European kingdoms as well as those kingdoms’ statutes. The texts that these manuscripts preserve have had formative influence on subsequent developments in law in English-speaking countries, Europe, and Latin America. The manuscripts in the collection also contain significant historical evidence, including fine artwork, annotations, and evidence of use by legal practitioners over the centuries.

Roman law, as it was taken up and developed over the course of the Middle Ages, is represented in the collection in several manuscripts of Justinian’s Institutes, as well as commentaries and notes on that document.

Canon law, the legal system of the Catholic Church, was a transnational body of law that united Western Europe especially following that body of law’s formalization and expansion from the 12th century onward. The Law Library possesses several early manuscripts of Gratian’s Decretum and the Liber Extra or Liber Decretalium of Gregory IX. In addition to these, it has other collections of canon law material in the form of commentaries, diocesan regulations and confessors’ manuals. 

English legal manuscripts in the collection include four 14th century manuscripts of Statuta Vetera, the Statutes of England from Magna Carta onward; it also contains two manuscripts of the so-called Statuta Nova, containing the laws of England from the reign of Edward III onward, as well as a manuscript of the thirteenth century work called Britton, or De Legibus Angliae – On the Laws of England, formerly attributed to Johannes Britton, dating to ca. 1390.

The Law Library’s collection includes some items that are especially worthy of note. Among the visually outstanding items in this collection are an anonymous French translation of the Institutes of Justinian (ca. 1280); Honore Bonet’s L’Arbe des Batailles, (MS. 14th c); the Grand Coustumier de Normandie (1450-1470); and Johannes de Imola’s Lectura on the Decretals of Gregory IX (ca. 1431-1447). An interesting English item from the point of view of association is the Law Library’s only manuscript of the Year Book reports, which are reports of pleadings in cases decided in English courts from the reign of Edward I (1272-1307), to that of Henry VIII (1509-47). That manuscript is in part or in whole in the hand of Anthony Gell (d. 1583), a law reporter who was active from the reign of Edward VI and into the reign of Elizabeth I. Perhaps the most extraordinary item in this regard is a consilium in the hand of the renowned medieval legal authority Baldo de Ubaldi (1327?-1400).

The materials in this collection were acquired during two periods of intensive collection development. The first, during which 60 of these items were added to Law Library collections, took place between 1930 and 1950, during a period that benefited from a significant expansion of the Law Library’s book acquisition budget over previous years. The second period, beginning with 2011 and lasting until the present time, has seen the addition of tens of medieval manuscripts to the Law Library’s collection.
Some of these items have been recorded in surveys of medieval manuscripts, such as Seymour de Ricci’s Census of medieval and renaissance manuscripts in the United States and Canada (New York, The H. W. Wilson Company, 1935-40); and John H. Baker’s English legal manuscripts in the United States of America: a descriptive list (London: Selden Society, 1985). Some items were also described in Svato Schutzner’s Medieval and Renaissance manuscript books in the Library of Congress: a descriptive catalog (Washington: The Library of Congress: For sale by the Supt. of Docs., U.S. G.P.O., 1989-<1999 >).

The history of law in the Western Middle Ages represents the gradual marriage of local customary law and national codes with learned bodies of law that had a transnational character. This amalgamation introduced a sophistication that permitted Europeans to meet the administrative needs of a society growing rapidly in power and complexity. The resulting record of that transformation and the literature it produced is a body of legal creativity and inventiveness that supplied the origins of such decisive modern ideas as constitutionalism, natural rights and the rule of law.