Collection
- Marvin and Sybil Weiner Spirit of America Collection Pamphlets -- Essays & Reports, 1745-19831
- Marvin and Sybil Weiner Spirit of America Collection Pamphlets -- Foreign Language, 1565-19421
- Marvin and Sybil Weiner Spirit of America Collection Pamphlets -- Miscellaneous, 1755-19901
- Marvin-Green sheet music collection, 1880-19801
- Mary Leonard Phelps Collection, circa 1911-19461
- Mary Mendenhall Wood Collection, 1901-1967, bulk 1964-19671
- Mary and Julia Pelot Collection, 1925-19451
- May Ryburn Papers, 1880-2003, bulk 1925-20031
- McCown, Alberta Lee Davis, Papers, 1913-1965, Date acquired: 07/00/19811
- McGill Family Papers, 1836-1962, Date acquired: 10/29/19821
- Melvin Rackleff collection, 1912-2005, Date acquired: 11/12/1999, bulk 1944-19461
- Memoranda on Tavares, 1875-1925, Date acquired: 09/01/19631
- Mercantile store records, 1915-19431
- Metzger, Lewis William, Papers, 1921-1985, Date acquired: 08/00/19891
- Michael A. Spencer Collection on Henry Nehrling, 1894-19971
- Michael A. Spencer Collection on Theodore Mead, 1887-19391
- Michael E. Krauss collection, 1882-1989, Date acquired: 00/00/2018, bulk 1958-19891
- Miles L. Hanley collection, 1918-1954, Date acquired: 06/24/19801
- Milton Charles Brown papers, 1925-1954, Date acquired: 2018-03-03, bulk 1943-19451
- Miriam and Roman Waldman Music Collection, 1900-19401