- RADMILOVIC, PAUL (1886 - 1968), swimmer
- RADNOR, 2nd Earl of - see BODVEL
- RAFF ap ROBERT (fl. 1550) Cilgwyn, Bachymbyd, 'a free holder of Dyffryn Clwyd' and a non-professional poet
- RAGLAN, 4th Baron - see SOMERSET, FITZROY RICHARD
- RAHEL O FÔN - see DAVIES, RACHEL
- RAINE, ALLEN - see PUDDICOMBE, ANNE ADALISA
- RANDALL, HARRY - see RANDALL, HENRY JOHN
- RANDALL, HENRY JOHN (1877 - 1964), lawyer and historian
- RANDLES, EDWARD (1763 - 1820), blind harpist and organist
- RANDLES, ELIZABETH (1801? - 1829), harpist and pianist
- RANKIN, SUSANNAH JANE (1897 - 1989), minister (Cong.) and missionary in Papua
- RATHBONE, MARY FRANCES (d. 1937) - see RATHBONE, WILLIAM
- RATHBONE, WILLIAM (1819 - 1902), philanthropist
- RAVENSCROFT family Ravenscroft,
- RECORDE, ROBERT (c. 1512 - 1558), mathematician and physician
- RECORDE, ROBERT (d. 1558)
- REDMOND, THOMAS (1745? - 1785), miniaturist
- REES family Ton
- REES, ABRAHAM (1743 - 1825), encyclopaedist
- REES, ALAN WILLIAM (1941 - 2005), Benedictine monk and musician
- REES, BOWEN (1857 - 1929), missionary
- REES, BRINLEY RODERICK (1919 - 2004), classical scholar, educationist and university college principal
- REES, CALEB (1883 - 1970), inspector of schools and author
- REES, DANIEL (1855 - 1931), journalist
- REES, DANIEL (1793 - 1857), cleric and hymnwriter
- REES, DAVID (1918 - 2013), mathematician
- REES, DAVID (1683? - 1748), Baptist minister and theological writer
- REES, DAVID (1751 - 1818), Calvinistic Methodist minister
- REES, DAVID (1801 - 1869), Congregational minister, and editor
- REES, Dr. DAVID (1818 - 1904) Bronnant, preacher with the Calvinistic Methodists
- REES, DAVID JAMES (1913 - 1983), golfer and author
- REES, DAVID RICE (1787 - 1856), printer - see REES
- REES, DOROTHY MARY (1898 - 1987), Labour politician and alderman
- REES, EBENEZER (1848 - 1908), printer and publisher
- REES, EDWARD WALTER (Gwallter Dyfi; 1881 - 1940), bank manager and bearer of the Gorsedd sword
- REES, EVAN (Dyfed; 1850 - 1923), Calvinistic Methodist minister, poet, and archdruid of Wales
- REES, FLORENCE GWENDOLEN (1906 - 1994), helminthologist (one who studies worms, particularly parasitic ones), Professor of Zoology
- REES, GABRIEL (1757 - 1807), Baptist minister
- REES, GEORGE (d. 1795), Baptist minister
- REES, GEORGE (1873 - 1950), poet and hymnwriter
- REES, GEORGE OWEN (1813 - 1889), physician - see REES, JOSIAH
- REES, HENRY (1798 - 1869), most famous minister among the Calvinistic Methodists in his day
- REES, HENRY (1837 - 1908), minister - see REES, WILLIAM
- REES, J. T. - see REES, JOHN THOMAS
- REES, JAMES (1803 - 1880), printer and publisher
- REES, Sir JAMES FREDERICK (1883 - 1967), Principal of the University College at Cardiff
- REES, JOHN (1770 - 1833), Calvinistic Methodist minister
- REES, JOHN CONWAY (1870 - 1932), Rugby footballer
- REES, Sir JOHN MILSOM (1866 - 1952), surgeon and laryngologist
- REES, JOHN SEYMOUR (1887 - 1963), minister (Congl.) and author