McGill Rare Books and Special Collections holds more than 235 medieval -era manuscripts, spanning from the 9th to the 15th century. Finding aids are available. upon request.
HORÆ: Collection of Books of Hours (McGill Rare Books and Special Collections): features 37 Books of Hours in both manuscript and printed form, from the 14th to 16th centuries.. Bilingual French and English.
Descriptions available in print and online here:
Catalogue Raisonné Des Livres D'heures Conservés Au Québec. Québec Presses de l'Université du Québec, 2018.
BVMM: Bibliothèque virtuelle des manuscrits médiévaux (CNRS, France): a virtual library of medieval manuscripts in French Libraries by the Institut de recherche et d’histoire des texts in Paris.
MANUSCRIPTA (Bibliothèque nationale de France): Manuscrits sans confinement - nouvelle rubrique en forme de blog.
GALLICA (Bibliothèque nationale de France): Collections par thèmes.
Online subject guide to Manuscripts and Archives (British Library): subject guides.
Illuminated Manuscripts (British Library): Selections of illuminated manuscripts.
DigiVatLab (Vatican Library): Access to the Vatican Library’s digitized collections: manuscripts, incunabula, archival materials and inventories as well as graphic materials, coins and medals, and printed materials.
Medieval and Early Modern Manuscripts Collection (Harry Ransom Center): The Medieval and Early Modern Manuscripts Collection contains 215 medieval or Renaissance manuscripts that date between the 11th and 17th centuries.
Medieval Manuscript Manual. This site offers basic information about Medieval Manuscripts, including their production, structure and function. There is also a glossary. The site was created by the Department of Medieval Studies at Central European University, Budapest.
Understanding Illuminated Manuscripts: A Guide to Technical Terms Illustrated glossary by Michelle Brown
How Parchment is Made (BBC video, 4 min): Wim Visscher shows Dr Stephen Baxter how to make parchment from animal skins
Making Manuscripts (Getty Center, 6 min video).
Making Manuscripts in Medieval England and France, 700–1200 (British Library).