Printed items, typescripts, press cuttings, and some letters, 1963-1994, on the Welsh language. They include material on the 1963 Report of the Council for Wales and Monmouthshire, teaching through the medium of the Welsh language in the University of Wales, parliamentary debates on the status of the Welsh language, broadcasting, bilingual road signs, the use of the Welsh language in the law courts, the Welsh language and the education system, the 1971 Census, publishing in the Welsh language, and Welsh language television.

Minutes, 1952-1955, agendas and papers for meetings of the Committee, 1952-1955, and general papers and correspondence, 1951-1959.

Mainly the typescript texts of lectures and talks given by Sir Goronwy Daniel, 1969-1993, to the inter-collegiate eisteddfod 1969; the Urdd National Eisteddfod, 1969; 'General Lectures for First-Year Students' at the University College of Wales, Aberystwyth, 1969; 'Living in Wales' (the Principal's Annual Address to first year students at the University College of Wales, Aberystwyth); the opening of the industrial exhibition at the Ammanford National Eisteddfod, 1970; a talk on 'Welsh Nationalism' at Chester, March 1970; an address to the Congress of Celtic Youth, November 1970; 'Addysg Uwch drwy gyfrwng y Gymraeg', 3 July 1971, subsequently published in Yr Athro, September 1971; 'Welsh Nursery Schools: an important movement' to the St Davids Day dinner of the Haverfordwest Cymmrodorion Society, 4 March 1974, etc. The file also includes similar material prepared by Dr Douglas Bassett, 1987-1989.

Includes correspondence with T.H. Parry-Williams, 1929, about teaching Welsh through the medium of Welsh in Aberystwyth.

Papers of the Board for Welsh Medium Teaching, 1980-1991, agendas and reports of the Board's Academic Committee, 1981-1988, and papers of Working/Planning Groups set up by the Board, 1985-1990.

Minutes of the standing committee, 1931-1939, and general papers and correspondence, 1923-1939, including registrar's reports.

Committee minutes, 1930-1935, agendas and papers for meetings, 1930-1935, and subject files, 1931-1935.

Llythyrau a chardiau, 1980, a anfonwyd at Gwynfor Evans yn dilyn ei lwyddiant yn darbwyllo'r llywodraeth i ildio dros fater sicrhau S4C fel sianel ar gyfer rhaglenni Cymraeg eu hiaith./Letters and cards, 1980, sent to Gwynfor Evans to congratulate him on his success in persuading the government to back down over designating S4C as the channel reserved for Welsh language television programmes.

Yn cynnwys papurau, 1952-1955, yn tarddu o gyfarfodydd pwyllgor a sefydlwyd i ystyried priodoldeb sefydlu coleg Cymraeg ei iaith o fewn Prifysgol Cymru./ Includes papers, 1952-1955, deriving from the proceedings of a committee established to consider the suitability of establishing a Welsh medium college within the University of Wales.

Research and personal papers of Dafydd Jenkins, comprising correspondence, drafts and other papers relating to his articles and books, [1937]-1997; correspondence, 1935-1989, on subjects including legal and academic matters, 1972-1991, evening classes given by DJ on agricultural subjects, 1944-1957, the New Welsh Language Act Campaign, 1983-1987, broadcasting, 1950-1963, and publishing, 1942-1989; papers concerning the Welsh language, 1972-1992; papers, 1938-1939, relating to the Welsh Language Petition, including circulars and newsletters; papers relating to British Legal History Conferences, 1971-1995, and International Congresses of Celtic Studies, 1967-1975; correspondence, minutes and other papers relating to organisations including Plaid Cymru, the National Eisteddfod, Undeb Cymru Fydd, the Sociological Group of the Church in Wales and the Milk and Dairies Tribunal for Wales, 1947-1979; ecumenical papers relating to Siloh Calvinist Methodist Chapel, Aberystwyth, 1958-1970; miscellaneous papers relating to various associations, societies, and organizations, 1969-1996; printed material relating to Plaid Cymru and Denmark, 1938-1970.

Minutes of the Committee, 1974-1975, agendas and papers for meetings, 1974-1975, and general papers mainly concerning the setting up of the Working Party, 1973-1975, including the Committee's final report.

Registrar's papers relating to the work of the Committee, 1980-1982, including some correspondence from 1979, and papers relating to the fourth television channel in Wales.

Minutes of the committee, 1970-1979, agendas, papers and Registrar's correspondence, 1970-1980, Registrar's administrative papers, 1967-1980, and miscellaneous papers, 1963-1980.

Papers relating to Richard Rees ('Maldwyn', 1851-1927), of Machynlleth, Montgomeryshire, and Edward Walter Rees, ('Gwallter Dyfi', 1881-1940), of Carmarthen, including correspondence, 1874-1940; printed materials, 1866-1937; papers relating to the National Eisteddfod and the Gorsedd of Bards, 1909-1939; papers relating to the National Petition on the Legal Status of the Welsh Language, 1938-1939; papers relating to Maengwyn Calvinistic Methodist Chapel, Machynlleth, 1875-1920; and various papers relating to manifold aspects of Machynlleth life.