Former Owner
- Monsieur de Bel Air1
- Moor of Ireton1
- Morot1
- Morton Davis Mitchell1
- Mount Zion Abbey1
- Mr. Hals1
- Mrs. E.J. Hooper1
- Mrs. F. W. Bartlett1
- Mrs. Turnbull1
- Muriel Agnes Fry1
- Murray Anthony Potter1
- Museo Cavaleri1
- N. Pauli1
- Nathan Comfort Starr1
- Nathaniel Castleton Stephen Poyntz1
- Nathaniel Dunbar1
- Nathaniel G. Snelling1
- Nell Wheeler1
- Nettie Goldsmith Naumburg1
- Neustift Abbey1