| Surname | Given name | Location | Item |
| Mackay | Robert | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| Macomber | James P. | Massachusetts | 1890 New Bedford, Massachusetts photo album: James Stowe Macomber (1870–1958) |
| Macomber | James Stowe | Massachusetts | 1890 New Bedford, Massachusetts photo album: James Stowe Macomber (1870–1958) |
| Macomber | Richard | Massachusetts | 1890 New Bedford, Massachusetts photo album: James Stowe Macomber (1870–1958) |
| Macomber | William | Massachusetts | 1890 New Bedford, Massachusetts photo album: James Stowe Macomber (1870–1958) |
| Macy | George I. | Massachusetts | 1890 New Bedford, Massachusetts photo album: Helen Curtis Hervey (1872–1923) |
| Mahoney | William | Ohio | 1841-1860 Washington Presbyterian Church Minutes, Guernsey County, Ohio |
| Marshall | Bessie | Kentucky | Pearl H. Mountjoy Autograph Book |
| Marshall | Hiram | Massachusetts | 1890 New Bedford, Massachusetts photo album: Laura Moulton Benjamin (1871 – 1928) |
| Marshall | Sarah Young | Kentucky | Pearl H. Mountjoy Autograph Book |
| Marshall | Seth | Ohio | Morgan County, Ohio 1864 Union Presidential Ticket ballot |
| Mary Helen Ellis | Mary Helen | Kentucky | Cadiz High School, Trigg County, Kentucky, 1924 commencement exercises program |
| Mashburn | Harvey S. | Kentucky | Cadiz High School, Trigg County, Kentucky, 1924 commencement exercises program |
| Mason | Nina Mae | Kentucky | Cadiz High School, Trigg County, Kentucky, 1924 commencement exercises program |
| Mathew | John A | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| Matthews | Stanley | Ohio | Morgan County, Ohio 1864 Union Presidential Ticket ballot |
| Mayhew | Allen G. | Massachusetts | 1890 New Bedford, Massachusetts photo album: Irene Mayhew Bassett (1872–1959) |
| Mayhew | Almira D. | Massachusetts | 1890 New Bedford, Massachusetts photo album: Irene Mayhew Bassett (1872–1959) |
| Mayhew | Harriet | Massachusetts | 1890 New Bedford, Massachusetts photo album: Irene Mayhew Bassett (1872–1959) |
| McAdams | Hiram R. | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| McAdams | John T. | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| McBurney | Benjamin | Ohio | 1841-1860 Washington Presbyterian Church Minutes, Guernsey County, Ohio |
| McCausey | James Monroe | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| McClurg | William | Ohio | 1841-1860 Washington Presbyterian Church Minutes, Guernsey County, Ohio |
| McCollum | Aaron | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| McCombs | John H. | Ohio | Morgan County, Ohio 1864 Union Presidential Ticket ballot |
| McConkey | John | Ohio | 1841-1860 Washington Presbyterian Church Minutes, Guernsey County, Ohio |
| McCook | John | Ohio | Morgan County, Ohio 1864 Union Presidential Ticket ballot |
| McCord | Elihu R. | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| McCrane | Ann | Ohio | 1841-1860 Washington Presbyterian Church Minutes, Guernsey County, Ohio |
| McCreary | James | Ohio | 1841-1860 Washington Presbyterian Church Minutes, Guernsey County, Ohio |
| McCrillon | James | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| McCullah | Clinton | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| McCullah | James M. | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| McCullums | Isaac | Ohio | 1841-1860 Washington Presbyterian Church Minutes, Guernsey County, Ohio |
| McCurdy | John | Ohio | 1841-1860 Washington Presbyterian Church Minutes, Guernsey County, Ohio |
| McDerwell | William | Ohio | 1841-1860 Washington Presbyterian Church Minutes, Guernsey County, Ohio |
| McIntyre | Jennie M. | New York | Paul Marion and Pauline Mary Faulkner, October 1913 |
| McKemy | Donald | Missouri | Winifred Louise Hooper Family Photos, ca. 1905-1912, Trenton, Missouri |
| McKemy | Harold | Missouri | Winifred Louise Hooper Family Photos, ca. 1905-1912, Trenton, Missouri |
| McKemy | James | Missouri | Winifred Louise Hooper Family Photos, ca. 1905-1912, Trenton, Missouri |
| McKemy | Orah | Missouri | Winifred Louise Hooper Family Photos, ca. 1905-1912, Trenton, Missouri |
| McKemy | Orah “Stanley” | Missouri | Winifred Louise Hooper Family Photos, ca. 1905-1912, Trenton, Missouri |
| McKenna | Elizabeth J. | Pennsylvania | Faulkner Automotive Group of Philadelphia dealership nameplate |
| McNorman | Robert | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| McShall | William M. C. | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| Mercanton | Emma | Massachusetts | Marie Dupont Vuilleumier Bible,1904, Massachusetts |
| Merry | Andrew B. | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| Merry | Hogan | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| Merry | Prettyman | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| Merry | Robert T. | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| Metcalf Cheever | Elizabeth Inez Sarah | Massachusetts | 1890 New Bedford, Massachusetts photo album: George William Needham (1873–1965) |
| Miller | George W. | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| Miller | Hugh | Ohio | 1841-1860 Washington Presbyterian Church Minutes, Guernsey County, Ohio |
| Miller | Lewis | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| Miller | Nettie | Kentucky | Pearl H. Mountjoy Autograph Book |
| Milliken | Annie Clapp | Massachusetts | 1890 New Bedford, Massachusetts photo album: Annie Clapp Milliken (1872–1925) |
| Milliken | Frank | Massachusetts | 1890 New Bedford, Massachusetts photo album: Annie Clapp Milliken (1872–1925) |
| Milliken | George Henry, Jr | Massachusetts | 1890 New Bedford, Massachusetts photo album: Annie Clapp Milliken (1872–1925) |
| Milliken | Geroge Henry | Massachusetts | 1890 New Bedford, Massachusetts photo album: Annie Clapp Milliken (1872–1925) |
| Milliken | Hugh Emmons | Massachusetts | 1890 New Bedford, Massachusetts photo album: Annie Clapp Milliken (1872–1925) |
| Mills | Absalom “Abner” H. | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| Mitchell | Virginia Dare | Kentucky | Cadiz High School, Trigg County, Kentucky, 1924 commencement exercises program |
| Moore | Daniel W. | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| Moore | Daniel Webster, Jr | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| Moore | Elizabeth | Missouri | Cora Gabrielle Curns Smith photograph, ca. 1890s, St. Louis, Missouri |
| Moore | Samuel P., Judge | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| Moorefield | Mary Eleanor | Kentucky | Cadiz High School, Trigg County, Kentucky, 1924 commencement exercises program |
| Morrison | Joseph | Ohio | 1841-1860 Washington Presbyterian Church Minutes, Guernsey County, Ohio |
| Morrow | James | Ohio | 1841-1860 Washington Presbyterian Church Minutes, Guernsey County, Ohio |
| Morrow | William | Ohio | 1841-1860 Washington Presbyterian Church Minutes, Guernsey County, Ohio |
| Morse | Francis G. | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| Morse | Stephen | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| Mould | Delia Elizabeth | Massachusetts | 1890 New Bedford, Massachusetts photo album: Dr. George Everett Noble (1871–1899) |
| Mountfort | Priscilla | Maine | Aunt Priscilla Blanchard, ca. 1900, Portland, Maine |
| Mountjoy | Adolphus S., Rev. | Kentucky | Pearl H. Mountjoy Autograph Book |
| Mountjoy | Emerald | Kentucky | Pearl H. Mountjoy Autograph Book |
| Mountjoy | P. H. | Kentucky | Pearl H. Mountjoy Autograph Book |
| Mountjoy | Pearl | Kentucky | Pearl H. Mountjoy Autograph Book |
| Mountjoy | Ruby L. | Kentucky | Pearl H. Mountjoy Autograph Book |
| Mountjoy | William David “Cordy” | Kentucky | Pearl H. Mountjoy Autograph Book |
| Mowbray | John | Illinois | Greenville, Bond County, Illinois Poll Book, 16 May 1863 Election |
| Myrick | Sarah E. | Massachusetts | 1890 New Bedford, Massachusetts photo album: Caroline “Carrie” Bradford Nye (1871–1905) |