The Medieval and Early Modern Manuscripts Collection is a gathering of 215 Medieval or Renaissance manuscripts that date from the eleventh through the seventeenth centuries (bulk fifteenth through seventeenth centuries). Each item has a designated shelf mark (HRC 1 through HRC 225) and the items are organized by shelf mark number.

The manuscripts are written in several languages—including Dutch, English, Flemish, French, German, Greek, Hebrew, Italian, Latin, Middle English, Old English, and Spanish—and originated from a variety of countries—among them Austria, Bohemia, Bolivia, Byzantium, England, Flanders, France, Germany, Ireland, Italy, Netherlands, Portugal, Scotland, Spain, and the United States.

A substantial number of the texts are religious in content, though a number of other general subjects—including alchemy, architecture, astronomy, botany, cartography, classical literature, diplomacy, drama, genealogy, government, heraldry, history, kings and rulers, law, literature, mathematics, medicine, monasticism and religious orders, music, philosophy, poetry, science, and war—are also represented.

The earliest manuscript in the collection (HRC 29) is an eleventh-century codex of various texts compiled by Abbot Ellinger of Tegernsee, which is informally known as the since Bede's is the first text.

Because of their magnificent illuminations, the best-known medieval manuscripts in the collection are the books of hours, which contain prayers and offices used for devotion by the laity. Of the eleven books of hours in the collection, all of them dating from the fifteenth-century, seven came from France, which was a major center for the production of such books during that era. The most notable of these—known as the (HRC 8)—was made for the Belleville family, who, from the eleventh-century until the French Revolution, owned large land estates.

The collection also contains Biblical texts and service books used in church liturgy or worship, such as antiphonaries, breviaries, graduals, rituals, prayer books, psalters, and sermons. Among these is a fifteenth-century German ferial psalter and hymnal (HRC 114) important for its stylistic relationship to the Gutenberg Bible and early printed psalters.

Another major category of manuscripts includes classical texts, with copies of works by Cicero, Horace, Ovid, and Plato among others, as well as literary works from the Middle Ages, whose texts were composed by Chaucer, Dante, and Petrarch.

The historical documents in the collection represent a number of English, French, and Spanish monarchs as well as notable persons such as Oliver Cromwell, Martin Luther, John Milton, Sir Isaac Newton, Abraham Ortelius, and Sir Walter Raleigh. Among the types of documents present are charters, commonplace books, contracts, correspondence, decrees, deeds, diaries, government records, indentures, letters patent, minutes, notarial documents, notes, papal bulls, petitions, pontificals, receipts, reports, speeches, and writs.

A complete index with identified names of authors of texts or signers of documents in the collection is included in this finding aid.