Former Owner
- Michael Wodhull1
- Michaeliskonvent1
- Michiel family1
- Millard Meiss1
- Mirmellus Arnandi1
- Molin1
- Monasterium sanctorum quadraginta martyrum (Treviso Italy)1
- Morton Davis Mitchell1
- Mrs. Turnbull1
- Muhsinzâde Ömer Aǧa1
- Murray Anthony Potter1
- Musa Kâzım Efendi1
- Museo Cavaleri1
- Muḥammad Amīn al-Sabtī al-Alūsī Anṣārī1
- Muḥammad ʻAlī Ḥasanī Dāʻī al-Islāmī1
- Nathaniel Castleton Stephen Poyntz1
- Nathaniel G. Snelling1
- Nettie Goldsmith Naumburg1
- Neustift Abbey1
- Neuwerk Nunnery1