- Martini, Roberto2
- Martino, Barone di1
- Martino, Odino S., active 15th century1
- Martinus, Polonus, -12791
- Martyrologies1
- Mary Magdalene, Saint5
- Mary, Blessed Virgin, Saint26
- Mary, Blessed Virgin, Saint, in the liturgy1
- Marāḥ al-arwāḥ (Ibn Masʻūd, Aḥmad ibn ʻAlī)2
- Masjid al-Aqṣá (Jerusalem)1
- Masjid al-Nabawī al-Sharīf1
- Mass3
- Mass--Celebration3
- Massachusetts1
- Massachusetts--Boston149
- Massachusetts--Northampton4
- Massachusetts--Wellesley30
- Massachusetts--Williamstown20
- Masses1
- Masses, Unaccompanied1