- Manuscripts, Latin39
- Manuscripts, Latin (Medieval and modern)137
- Manuscripts, Medieval268
- Manuscripts, Oriental52
- Manuscripts, Persian77
- Manuscripts, Rajasthani1
- Manuscripts, Renaissance74
- Manuscripts, Sanskrit8
- Manuscripts, Spanish12
- Manuscripts, Turkish13
- Marginalia14
- Mark, Saint1
- Marriage2
- Marriage (Canon law)1
- Mary Magdalene, Saint1
- Mary, Blessed Virgin, Saint24
- Mary, Blessed Virgin, Saint, in the liturgy1
- Mashāriq al-anwār (Ṣaghānī, al-Ḥasan ibn Muḥammad)1
- Massachusetts--Boston154
- Massachusetts--Williamstown10