Former Owner
- Marsden J. Perry1
- Martin Schøyen1
- Marvin-L. Colker1
- Mary Stanley, Countess of Derby1
- Mary Talbot, Countess of Shrewsbury1
- Mary, Queen of Scots1
- Matthew Bloxam1
- Maurice Johnson1
- Melk Abbey1
- Michael Tomkinson1
- Miguel de Mayora1
- Milt Freudenheim1
- Mitchell Starrett Buck1
- Moissac Abbey1
- Monasterio de El Paular1
- Monastery at San Gregorio al Celio1
- Mortimer Loeb Schiff1
- Morton Parker Eden1
- Muhammed Ali Khan Wallajah1
- Mullā ʻAbbās Zīvarī1