| Surname | Country | State | County or Province | From | To | Member |
|---|---|---|---|---|---|---|
| Ramin | France | Provence-Alpes-Côte-d'Azur | Alpes-Maritimes | 1630 | 1703 | J009-1 |
| Ramm | Norway | Oslo and Hedmark Region | 1650 | 1950 | B023-1 | |
| Ramm | USA | Illinois | Cook County | 1880s | 1950 | B023-1 |
| Ramsay | Scotland | D013-2 | ||||
| Ramsay | USA | New Jersey | Hudson County | 1800 | present | D013-2 |
| Ramsay | USA | New York | Kings County (Brooklyn) | 1800 | present | D013-2 |
| Ravesies | France | Aquitaine | Gironde | 1760 | 1777 | J009-1 |
| Ravesies | Haiti | St Domingue | 1777 | 1791 | J009-1 | |
| Ravesies | USA | Pennsylvania | 1791 | 2007 | J009-1 | |
| Ravesies | USA | Alabama | 1791 | 2007 | J009-1 | |
| Ravesies | USA | Mississippi | 1791 | 2007 | J009-1 | |
| Ravesies | USA | Tennessee | 1791 | 2007 | J009-1 | |
| Ravesies | USA | North Carolina | 1791 | 2007 | J009-1 | |
| Redl | Austria | Burgenland, City Obverdrosen | 1745 | 1900 | H011-1 | |
| Redl | Austria | Burgenland, Post St Martin | 1745 | 1900 | H011-1 | |
| Redmond | USA | New York | Albany County | 1855 | 1870 | B003-1 |
| Redmond | USA | New York | Rensselaer County | 1855 | 1870 | B003-1 |
| Reely | USA | Wisconsin | Sauk County | 1850 | 1880 | A009-1 |
| Reely | USA | Iowa | Palo Alto County | 1870 | present | A009-1 |
| Reely | USA | Iowa | Cerro Gordo County | 1870 | present | A009-1 |
| Reeves | England | M025-1 | ||||
| Reeves | USA | Ohio | 1850 | M025-1 | ||
| Reeves | USA | Illinois | Piatt County | 1850 | present | M025-1 |
| Rehsteiner | Switzerland | Appenzell | Speicher | 1600 | 1880 | B018-1 |
| Rehsteiner | Switzerland | Trogen | 1600 | 1830 | B018-1 | |
| Reichelt | USA | Illinois | Cook County | 1920 | 1980 | B023-1 |
| Reidy | Ireland | County Limerick | Limerick City | 1840 | ? | B026-2 |
| Reilly | USA | 1845 | 1900 | B027-1 | ||
| Reiner | A010-1 | |||||
| Requier | France | Périgord | Dordogne | 1590 | 1679 | J009-1 |
| Reynaud | France | Provence-Alpes-Côte-d'Azur | Alpes de Haute Provence | 1640 | 1744 | J009-1 |
| Rice | USA | MO | St. Louis, Cape Girardo | 1865 | 1900 | B020-1 |
| Rice | England | 1600 | 1710 | F009-1 | ||
| Rice | USA | IL | Cook | B020-1 | ||
| Rice | USA | Massachusetts | 1710 | present | F009-1 | |
| Richardson | USA | Ohio | 1850 | 1861 | F009-1 | |
| Richardson | USA | Missouri | Pettis County | 1861 | present | F009-1 |
| Riddle | USA | Pennsylvania | Indiana County | 1858 | 1895 | N001-1 |
| Riddle | USA | Pennsylvania | Allegheny County | 1858 | 1895 | N001-1 |
| Riddle | USA | Washington | King County (Seattle) | 1895 | 1928 | N001-1 |
| Riemer | Prussia | Posen | 1850 | present | C008-1 | |
| Robbins | Ireland | bef 1820 | 1820 | M019-1 | ||
| Robbins | USA | Wisconsin | 1820 | present | M019-1 | |
| Roben | Germany | bef 1860 | 1860 | M019-1 | ||
| Roben | USA | Iowa | Grundy County | 1845 | present | M019-1 |
| Roben | USA | Iowa | Osceola County | before 1845 | present | M019-1 |
| Roberto | Italy | Albenga Imperia | Liguria | 1800 | 1840 | J009-1 |
| Robinson | K002-1 | |||||
| Rochford | Ireland | County Clare | 1861 | present | M023-1 | |
| Rochford | USA | Minnesota | Ramsey County (St. Paul) | M023-1 | ||
| Rock | Germany | 1700 | 1850 | B031-1 | ||
| Rockhold | USA | KS | W020-1 | |||
| Rockhold | USA | KS | ||||
| Roddy | Ireland | 1820 | 1840 | K027-1 | ||
| Roddy | USA | Pennsylvania | 1840 | 1878 | K027-1 | |
| Roebke | Germany | K019-1 | ||||
| Roeser | T013-1 | |||||
| Rogers | USA | Illinois | Jo Daviess County | bef 1830 | 1830 | D013-1 |
| Rogers | Northern Ireland | Monaghan | 1630 | 1830 | D013-1 | |
| Roginski | USA | Illinois | Cook County (Chicago) | S016-1 | ||
| Röhl | Germany | Pommerania | 1875 | 1990 | G015-1 | |
| Röhl | USA | Indiana | Lake County | 1875 | 1990 | G015-1 |
| Röhl | USA | Illinois | Cook County | 1875 | 1990 | G015-1 |
| Rohner | Switzerland | Appenzell | Reute | 1770 | 1860 | B018-1 |
| Rolfe | A010-1 | |||||
| Roller | Austria | Bohemia | Johnsdorf | 1854 | W008-1 | |
| Roller | USA | Wisconsin | Watertown County | 1854 | present | W008-1 |
| Roller | USA | Wisconsin | Dodge County | 1854 | present | W008-1 |
| Romag | Prussia | 1833 | 1854 | R003-1 | ||
| Romag | USA | Wisconsin | Fond du Lac County | 1854 | 1863 | R003-1 |
| Ros | France | Provence-Alpes-Côte-d'Azur | Alpes-Maritimes | 1670 | 1778 | J009-1 |
| Rosenbaum | USA | Wisconsin | Brown County | C006-1 | ||
| Rosenmeier | Germany | Bavaria | 1853 | W008-1 | ||
| Rosenmeier | USA | Wisconsin | Dodge County (Westford Twp) | 1853 | present | W008-1 |
| Rosenmeier | USA | Wisconsin | Beaver Dam County | 1853 | present | W008-1 |
| Rosenmeyer | Germany | Bavaria | 1853 | W008-1 | ||
| Rosenmeyer | USA | Wisconsin | Dodge County (Westford Twp) | 1853 | present | W008-1 |
| Rosenmeyer | USA | Wisconsin | Beaver Dam County | 1853 | present | W008-1 |
| Rosenthal | R002-1 | |||||
| Ross | USA | Massachusetts | Warren County | bef 1850 | D005-1 | |
| Ross | USA | Massachusetts | Worcester County | bef 1850 | D005-1 | |
| Ross | USA | Kansas | Douglas County | D005-1 | ||
| Rous | France | Provence-Alpes-Côte-d'Azur | Alpes-Maritimes | 1700 | 1784 | J009-1 |
| Rousset | France | Périgord | Dordogne | 1700 | 1784 | J009-1 |
| Rowe | USA | Massachusetts | Gloucester | 1675 | 1880 | P012-1 |
| Rowe | USA | New York | 1700 | 1810 | R008-1 | |
| Rowe | USA | Massachusetts | 1700 | 1810 | R008-1 | |
| Rowe | USA | Maine | 1675 | 1880 | P012-1 | |
| Ruch | Germany | Palatinate | D013-2 | |||
| Ruch | USA | Pennsylvania | Lehigh County | 1733 | present | D013-2 |
| Ruch | USA | Pennsylvania | Northumberland County | 1806 | present | D013-2 |
| Ruff | Germany | Baden | L008-1 | |||
| Ruff | USA | Pennsylvania | L008-1 | |||
| Ruprecht | Germany | B027-1 | ||||
| Russell | A010-1 | |||||
| Russell | Canada | Ottawa | Carleton County | 1835 | 1870 | B003-1 |
| Russell | USA | Illinois | Warren County | 1820 | 1900 | C022-1 |
| Russell | USA | Georgia | 1800 | J009-1 | ||
| Russell | Scotland | 1649 | 1870 | T009-1 | ||
| Russell | USA | Wisconsin | Oconto County (Oconto) | 1864 | 1912 | B003-1 |
| Russell | USA | Illinois | Henderson County | 1820 | 1900 | C022-1 |
| Russell | USA | Alabama | J009-1 | |||
| Russell | USA | Illinois | Cook County | 1870 | 1900 | T009-1 |
| Russell | USA | Washington | Pacific County | 1900 | 1930 | T009-1 |
| Russell | USA | Illinois | Cook County | 1860 | 1940 | C022-1 |
| Russell | USA | Florida | J009-1 | |||
| Russell | USA | Illinois | Lake County | 1870 | 1900 | T009-1 |
| Russell | USA | South Carolina | 2007 | J009-1 | ||
| Rust | USA | Wisconsin | Waukesha County | 1820 | 1970 | C022-1 |
| Rustichelli | Italy | Emilia Romagna | Ravenna | 1799 | 1908 | J009-1 |
| Rustichelli | France | Provence-Alpes-Côte-d'Azur | Alpes-Maritimes | 1882 | 1979 | J009-1 |
| Ruswick | Prussia | Silesia | J005-2 | |||
| Ryan | Ireland | Foxford | County Mayo | M014-1 |