Former Owner
- Milt Freudenheim1
- Milton S. Carothers1
- Minerva Kaiser1
- Minnis, Katherine1
- Moissac Abbey1
- Molin1
- Monasterio de El Paular1
- Monastery of Benevívere1
- Monastery of Saint Peter (Erfurt, Germany)1
- Monastery of San Bartolmeo, Arezzo, Tuscany1
- Monica Franklyn1
- Monsieur de Bel Air1
- Moor of Ireton1
- Moritz Dessauer1
- Morot1
- Mortimer Loeb Schiff1
- Morton Davis Mitchell1
- Mount Zion Abbey1
- Mrs. E.J. Hooper1
- Mrs. F. W. Bartlett1