Press cuttings of articles, poetry and miscellaneous notes by 'Rhuddenfab', including notes on 'eisteddfodau'; a series of seventy articles entitled 'Deugain Mlynedd yn Ôl' by 'Rhen O', i.e. 'Rhuddenfab'; and autograph letters to 'Rhuddenfab' from Rowland Williams ('Hwfa Môn'), Sir George Osborne Morgan, John Davies ('Taliesin Hiraethog'), William Jones ('Ehedydd Iâl'), J. Ceulanydd Williams ('Ceulanydd'), Richard Davies ('Mynyddog') and John Thomas ('Eifionydd'); etc.

An analysis of the National Eisteddfod music competitions, 1899-1908, giving subjects, adjudicators and prizes.

Papurau'r cymdeithasegydd Alwyn D. Rees, 1911-1974, yn cynnwys papurau'n ymwneud â Phrifysgol Cymru, yn bennaf â Choleg Prifysgol Cymru, Aberystwyth, 1920au-1974, gan gynnwys papurau'n ymwneud â'r comisiwn a sefydlwyd i archwilio strwythur ffederal Prifysgol Cymru yn y 1960au; papurau ynglŷn â lle'r Gymraeg yn y Brifysgol a'r ymgyrch i sefydlu neuadd Gymraeg i fyfyrwyr yn Aberystwyth,1967-1974; papurau'n ymwneud â llyfrau, erthyglau a darlithoedd Alwyn D. Rees, 1933-1973, a Chymdeithas yr Iaith Gymraeg, [c.1964]-1974; papurau'n ymwneud â Barn, 1966-1967; papurau'n ymwneud â darlledu yng Nghymru, 1938-1974; papurau'n ymwneud â'r diwydiant llechi yng Nghymru,1946; papurau'n ymwneud â gwleidyddiaeth yng Nghymru, 1911-1974; gohebiaeth gyffredinol, 1935-1974; a phapurau a gohebiaeth bersonol , 1930-1974 = Papers of the sociologist Alwyn D. Rees, 1911-1974, including papers relating to the University of Wales, mainly the University College of Wales, Aberystwyth, 1930s-1974, including papers relating to the commission established to examine the federal structure of the University of Wales in the 1960s; papers concerning the place of the Welsh language in the University and the campaign to establish a Welsh student hostel at Aberystwyth, 1967-1974; papers relating to the University of Malta, 1940-1951; Alwyn D. Rees's research papers, 1933-1973; papers relating to Alwyn D. Rees's books, articles and lectures, and further related research papers assembled by him, 1925-1974; papers relating to the Welsh language, 1952-1974, and 'Cymdeithas yr Iaith Gymraeg', [c. 1964]-1974; papers relating to 'Barn', 1966-1975; papers relating to broadcasting in Wales, 1938-1974; papers relating to the Welsh slate industry, 1946; papers relating to politics in Wales, 1911-1974; general correspondence, 1935-1974; and personal papers and correspondence, 1930-1974.

Cofnodion Urdd Gobaith Cymru, yn cynnwys papurau gweinyddol, yn eu plith adroddiadau a gohebiaeth, 1931-1990; cofnodion Pwyllgor, is-bwyllgorau a phaneli yr Urdd, 1939-1995, cofnodion ariannol, 1931-1996l, papurau yn ymwneud â theithiau tramor a drefnwyd gan Urdd Gobaith Cymru a Negeseuon Heddwch ac Ewyllys Da, 1931-1984; cofnodion, dogfennaeth ariannol ac arall perthynol i Gronfa Goffa O.M. Edwards, 1928-1976; papurau yn ymwneud â changhennau (adrannau ac aelwydydd), 1938-1960; gohebiaeth a phapurau yn ymwneud â chyrsiau a drefnwyd gan yr Urdd,1948-1965, a phapurau eraill yn ymwneud â'r cylchgronau, 1948-1990; trefniadau ar gyfer gwahanol wyliau, 1936-1995; cofnodion gweinyddol ac ariannol yn ymwneud â'r gwersylloedd yn Llangrannog a Glanllyn,1940-1995; deunydd printiedig, 1932-1963; llythyrau at O.M. Edwards, 1910-1920; cofnodion yn ymwneud â'r Cyngor, 1972-1991, a Chwmni yr Urdd, 1972-1989; cofnodion yn ymwneud ag aelodau staff, 1975-1995; gohebiaeth a thaflenni yn ymwneud ag Eisteddfod Genedlaethol yr Urdd,1930-1965; papurau yn ymwneud â Maes yr Eisteddfod, 1972-1985, seremonïau yr Eisteddfod, 1952-1982, sioeau'r theatr, 1981-1991, a chystadlaethau; a chofnodion yn ymwneud â threfnu pob un o'r Eisteddfodau Cenedlaethol, 1946-1996 = Records of Urdd Gobaith Cymru, comrpising general administrative papers, including reports and correspondence, 1931-1990; records of Urdd Committee, sub-committees and panels, 1939-1995; financial records, 1931-1996; papers relating to overseas trips organized by Urdd Gobaith Cymru and international meetings, 1931-1962; papers relating to the Messages of Peace and Goodwill, 1931-1984; minutes, financial and other records of the O. M. Edwards Memorial Fund, 1928-1976; papers relating to the Welsh School, Aberystwyth, 1939-1952; papers relating to branches (adrannau and aelwydydd), 1938-1960; correspondence and papers relating to courses organized by the Urdd, 1948-1965; papers relating to the annual conferences to discuss the Urdd's magazines, 1952-1973, and other pars relating to the magazines, 1948-1990; arrangements regarding various festivals, 1936-1995; administrative and financial records relating to the camps at Llangrannog and Glanllyn, 1940-1995; printed material, 1932-1963; letters addressed to O. M. Edwards, 1910-1920; records relating to the Council, 1972-1991, and Cwmni'r Urdd, 1972-1989; records relating to staff members, 1975-1995; correspondence and literature relating to the Urdd National Eisteddfod, 1930-1965; papers relating to the Eisteddfod Maes, 1972-1985, Eisteddfod ceremonies, 1952-1982, theatre shows, 1981-1991, and competitions; and records relating to the organisation of individual National Eisteddfodau, 1946-1996.