- Majolus, Saint, Abbot of Cluny, approximately 906-9941
- Mandeville, John, Sir1
- Manuscript maps1
- Manuscripts, Anglo-Norman1
- Manuscripts, Church Slavic1
- Manuscripts, Czech1
- Manuscripts, Digital1
- Maps1
- Margaret, Queen, consort of James IV, King of Scotland, 1489-15411
- Margaret, of Antioch, Saint1
- Marina, Saint1
- Marriage customs and rites, Medieval1
- Marriage law1
- Marriage--Moral and ethical aspects1
- Martino, Odino S., active 15th century1
- Mary, Blessed Virgin, Saint, in the liturgy1
- Masorah1
- Mass--Celebration1
- Mathematics, Medieval1
- Matthias I, King of Hungary, 1443-14901