Former Owner
- Matthias Corvinus1
- Maurice Johnson1
- Maximilian Henry of Bavaria1
- Mazliah Finzi1
- Maḥmūd bin Nāṣir1
- Maḥmūd ibn al-Shaykh al-Fattāḥ1
- Melk Abbey1
- Michael Tomkinson1
- Michaeliskonvent1
- Michel Chasles1
- Michele Amari1
- Michiel family1
- Millard Meiss1
- Mobed Framji Fardunji Madan1
- Mobed Hormazdyar Mobed Khodabaksh1
- Mohammed bin Hamed bu Osman1
- Monasterio de El Paular1
- Moritz Dessauer1
- Moritz Joseph Johann von Dietrichstein1
- Morris H. Morgan1