- Magic--Religious aspects--Christianity1
- Manicules1
- Manners and customs1
- Manuscripts, Catalan1
- Manuscripts, English (Middle)1
- Mass--Celebration1
- Massachusetts--Williamstown1
- Medea, consort of Aegeus, King of Athens (Mythological character)1
- Medicine1
- Medicine, Magic, mystic, and spagiric1
- Medicine--Formulae, receipts, prescriptions1
- Mehmed II, Sultan of the Turks, 1432-14811
- Mensural notation1
- Metaphysics1
- Middle East1
- Middle East--Jerusalem1
- Miniature books1
- Monasteries1
- Monasterio de San Jerónimo de Monte Olivete (Sant Pere de Ribes, Spain)1
- Monasterio de San Jerónimo de la Murtra (Badalona, Spain)1