| Surname | Country | State | County or Province | From | To | Member |
|---|---|---|---|---|---|---|
| Madigan | Ireland | County Limerick | Limerick City | 1809 | 1870 | B026-2 |
| Madigan | USA | Illinois | Cook County (Chicago) | 1870 | present | B026-2 |
| Maestralle | France | Provence-Alpes-Côte-d'Azur | Alpes-Maritimes | 1570 | 1650 | J009-1 |
| Magowan | USA | Virginia | 1740 | 1858 | S029-1 | |
| Magueur | France | Périgord | Dordogne | 1650 | 1771 | J009-1 |
| Maher | Ireland | County Carlow | O004-1 | |||
| Majewski | Austria/Hungary/Poland | Barcia Parish | Nowy Sacz | 1893 | 1912 | R003-1 |
| Majewski | USA | Illinois | Cook County | 1912 | 1959 | R003-1 |
| Maliorat | France | Périgord | Dordogne | 1700 | 1815 | J009-1 |
| Malmberg | Sweden | Vittsjö | Kristianstad | Bef 1881 | B019-1 | |
| Malmberg | USA | Massachusetts | 1881 | ? | B019-1 | |
| Malmberg | USA | New York | 1881 | ? | B019-1 | |
| Malmberg | USA | Illinois | 1881 | ? | B019-1 | |
| Maloney | Ireland | Clare County | 1800 | 1860 | M023-1 | |
| Mankopf | M020-1 | |||||
| Manquen | Poland | 1775 | present | I002-1 | ||
| Manquen | USA | Illinois | Cook County | 1775 | present | I002-1 |
| Mansfield | USA | Maryland | 1760 | A007-1 | ||
| Mansfield | USA | Ohio | 1760 | A007-1 | ||
| Manz | A010-1 | |||||
| Marc/Marca/Marco | France | Provence-Alpes-Côte-d'Azur | Alpes-Maritimes | 1590 | 1717 | J009-1 |
| Marconnet | A010-1 | |||||
| Margherio | Italy | 1860 | present | W006-1 | ||
| Margherio | USA | Illinois | Bureau County | 1860 | present | W006-1 |
| Margherio | USA | Illinois | Piedmont County | 1860 | present | W006-1 |
| Markett | USA | Maryland | Washington County | 1700s | A001-1 | |
| Markowich | Romania | Botosani | K010-1 | |||
| Markowski | Poland | Gruta | 1775 | 1875 | S017-1 | |
| Marquardt | W008-1 | |||||
| Marrules | Poland | Blonie | 1850 | present | H014-1 | |
| Marsh | USA | New York | 1830 | 1870 | F008-1 | |
| Marshall | Poland | 1875 | Present | K026-1 | ||
| Marshall | Germany | 1875 | Present | K026-1 | ||
| Marthaler | A010-1 | |||||
| Martin (1) | France | Provence-Alpes-Côte-d'Azur | Alpes-Maritimes | 1476 | 1700 | J009-1 |
| Martin (2) | France | Provence-Alpes-Côte-d'Azur | Alpes-Maritimes | 1600 | 1817 | J009-1 |
| Martindale | USA | Indiana | Miami county | B031-1 | ||
| Marton | Austria-Hungry | Myjava | 1850 | Present | H014-1 | |
| Mascarella | S003-1 | |||||
| Mathis | USA | Texas | S016-1 | |||
| Maxfield | USA | Pennsylvania | 1830 | 1920 | F008-1 | |
| May | USA | California | Stanislaus County | 1870 | 1950 | K021-1 |
| May | USA | Arkansas | Johnson County | 1840 | 1886 | K021-1 |
| Mc Kell | USA | Mississippi | J009-1 | |||
| Mc Kell | USA | Tennessee | J009-1 | |||
| Mc Kell | USA | Georgia | J009-1 | |||
| McCaffrey | Ireland | North | A002-1 | |||
| McCarthy | Ireland | County Waterford | L008-1 | |||
| McCarthy | M031-1 | |||||
| McCarthy | Ireland | bef 1860 | N001-2 | |||
| McCarthy | USA | Illinois | L008-1 | |||
| McCarthy | USA | Illinois | Cook County | 1860s | present | N001-2 |
| McCarthy | USA | Illinois | DuPage County | 1860s | present | N001-2 |
| McCarthy | USA | Illinois | Kane County | 1860s | present | N001-2 |
| McCarthy | USA | Illinois | Will County | 1860s | present | N001-2 |
| McClain | M020-1 | |||||
| McClary | USA | Pennsylvania | L008-1 | |||
| McClory | Ireland | County Down | Bef 1840 | 1850 | M024-1 | |
| McClory | USA | Pennsylvania | 1840 | 1890 | M024-1 | |
| McClory | USA | Ohio | 1840 | present | M024-1 | |
| McCloskey | USA | Pennsylvania | 1830 | 1920 | F008-1 | |
| McCloskey | Ireland | 1824 | 1848 | K027-1 | ||
| McCloskey | USA | Pennsylvania | 1848 | present | K027-1 | |
| McConnell | USA | Pennsylvania | L008-1 | |||
| McCully | USA | Mississippi | Lee County | 1775 | 1927 | B018-1 |
| McCully | USA | South Carolina | 1775 | 1927 | B018-1 | |
| McGovern | Ireland | Dowra | County Cavan | M014-1 | ||
| McGovern | Ireland | County Fermanagh | Fermanagh | before 1830 | M019-1 | |
| McGovern | M027-1 | |||||
| McGovern | M014-2 | |||||
| McGovern | USA | Wisconsin | about 1845 | present | M019-1 | |
| McGuire | USA | Maryland | A007-1 | |||
| McGuire | USA | Pennsylvania | A007-1 | |||
| McGuire | USA | Ohio | A007-1 | |||
| McHenry | Ireland | County Antrim | Antrim | 1850 | T004-2 | |
| McIntyre | Ireland | County Sligo | Kilmacteigue, Lislea | 1840 | 1904 | B026-2 |
| McIntyre | USA | Illinois | Cook County (Chicago) | 1904 | present | B026-2 |
| McKibben | Northern Ireland | 1750 | M025-1 | |||
| Mckibben | USA | Ohio | 1815 | 1860 | M025-1 | |
| McKibben | USA | Illinois | Edwards County | M025-1 | ||
| McLaughlin | Ireland | 1840 | 1860 | K027-1 | ||
| McLaughlin | Ireland | before 1845 | 1845 | M019-1 | ||
| McLaughlin | USA | Pennsylvania | 1860 | 1915 | K027-1 | |
| McLaughlin | USA | Wisconsin | about 1845 | present | M019-1 | |
| McNulty | Ireland | County Mayo | O004-1 | |||
| Mead | USA | Massachusetts | 1600 | 1850 | M017-1 | |
| Mead | USA | New York | 1600 | 1850 | M017-1 | |
| Meadows | USA | Virginia | 1760 | 1890 | S029-1 | |
| Meadows | USA | West Virginia | 1760 | 1890 | S029-1 | |
| Meekins | USA | Maryland | Somerset County | 1760 | 1830 | K008-1 |
| Meekins | USA | Ohio | Ross County | 1810 | 1830 | K008-1 |
| Meiring | Prussia | 1804 | M001-1 | |||
| Meiring | USA | Ohio | Mercer County | 1804 | 1915 | M001-1 |
| Melan/Mellan | France | Provence-Alpes-Côte-d'Azur | Alpes-Maritimes | 1550 | 1833 | J009-1 |
| Melcher | USA | Illinois | Kane County | B016-1 | ||
| Mera | France | Provence-Alpes-Côte-d'Azur | Alpes-Maritimes | 1612 | 1714 | J009-1 |
| Merdian | Germany | M026-1 | ||||
| Merdian | USA | Michigan | M026-1 | |||
| Merillou | France | Périgord | Dordogne | 1699 | 1784 | J009-1 |
| Merrill | USA | New York | Washington County | 1826 | F008-1 | |
| Merrill | USA | New York | Jefferson County | 1826 | F008-1 | |
| Merry | USA | Massachusetts | 1700 | 1850 | M017-1 | |
| Merry | USA | New York | 1700 | 1850 | M017-1 | |
| Messinger | Germany | Wurtemburg | Weinsburg | 1850 | H022-1 | |
| Metcalf | USA | Maine | Bef 1800 | 1900 | P012-1 | |
| Meuer | Germany | R002-1 | ||||
| Meyer | R002-1 | |||||
| Mikula | Czechoslavia | Bratislava | 1 | 1965 | K028-1 | |
| Miller | USA | IL | Lake and Kane Counties | D011-1 | ||
| Miller | England | M025-1 | ||||
| Miller | USA | Illinois | Piatt County | M025-1 | ||
| Miller | USA | Illinois | Macon County | 1880 | M025-1 | |
| Miller | USA | Texas | 1900 | M025-1 | ||
| Miner | USA | Illinois | Cook County | S033-1 | ||
| Mitchell | England | 1850 | M025-1 | |||
| Mitchell | USA | Illinois | Edwards County | 1850 | present | M025-1 |
| Mohr | USA | Indiana | Shelby county | C006-1 | ||
| Mohr | T013-1 | |||||
| Molloy | Ireland | Foxford | County Mayo | M014-1 | ||
| Moon | A010-1 | |||||
| Moon | USA | Pennsylvania | Allegheny County | 1830 | 1880 | N001-1 |
| Moore | Northern Ireland | Monaghan | 1630 | 1830 | D013-1 | |
| Moore | USA | Illinois | Jo Daviess County | 1830 | 1900 | D013-1 |
| Moore | USA | Pennsylvania | Northumberland County | 1850 | present | D013-2 |
| Moore | USA | Pennsylvania | Columbia County | 1850 | present | D013-2 |
| Moore | USA | Ohio | Champaign County | 1820 | present | H012-1 |
| Moreland | Ireland | C002-1 | ||||
| Morgan | USA | Indiana | Warrick County | 1815 | 1830 | S009-1 |
| Morraglia | France | Provence-Alpes-Côte-d'Azur | Alpes-Maritimes | 1590 | 1721 | J009-1 |
| Morris | USA | Pennsylvania | Greene County | 1806 | present | H018-1 |
| Morris | USA | North Carolina | Bertie County | 1750 | 1810 | K021-1 |
| Morris | USA | Virginia | P013-1 | |||
| Morris | USA | Kentucky | Graves County | 1820 | 1900 | K021-1 |
| Morrison | Scotland | Islay | 1800 | 1860 | B031-1 | |
| Morrow | USA | Louisiana | Rapides Parish | 1800's | C017-1 | |
| Motycka | USA | Illinois | 1889 | 1982 | J009-1 | |
| Moyer | S003-1 | |||||
| Mross | C014-1 | |||||
| Mroz | C014-1 | |||||
| Muche | Germany | Rhineland or Silesia | 1839 | 1912 | O001-1 | |
| Muche | USA | Minnesota | Hennepin County | 1839 | 1912 | O001-1 |
| Muer | Germany | M026-1 | ||||
| Muer | USA | Michigan | M026-1 | |||
| Mulchrone | Ireland | Newport | County Mayo | M014-1 | ||
| Munn | A010-1 | |||||
| Munroe | D002-1 | |||||
| Murat | France | Périgord | Dordogne | 1679 | 1867 | J009-1 |
| Murat | France | Gascogne | Gers | 1868 | 1903 | J009-1 |
| Murat | France | Provence-Alpes-Côte-d'Azur | Alpes-Maritimes | 1904 | 2007 | J009-1 |
| Murphy | Ireland | County Carlow | O004-1 | |||
| Musgrave | USA | Pennsylvania | Lancaster County | 1746 | 1776 | S009-1 |
| Musgrave | USA | Kentucky | Muhlenberg County | 1802 | 1825 | S009-1 |
| Musgrave | USA | Indiana | Warrick County | 1813 | present | S009-1 |
| Musial | Poland | Wyrsysk | 1775 | 1875 | S017-1 | |
| Myers | Germany | C002-1 |