Papurau'r Parch. William Rhys Watkin, yn cynnwys nodiadau pregethau a phapurau eraill,1899-1936; gohebiaeth, 1878-1948, blwyddlyfrau printiedig Undeb Bedyddwyr Cymru yn cynnwys cofnodion gan WRW, 1891-1945; nodiadau ymchwil ac erthyglau ar Bedo Brwynllys, y Parch. E. T. Jones, a hanes y Bedyddwyr, 1909-[1945], a llyfr nodiadau Pwyllgor yr Eisteddfod Genedlaethol, Llanelli,1928-1931; a chofnodion a gasglwyd ganddo, gan gynnwys cofnodion a chyfrifon eglwysi'r Bedyddwyr yn sir Gaerfyrddin a Morgannwg, 1843-930; nodiadau pregethau a phapurau eraill Richard Davies ('Yr Hen Belican'),1816-1873; papurau a llyfrau nodiadau amrywiol yn ymwneud â'r Bedyddwyr Cymraeg, 1787-1896; a phapurau Thomas Jones, morwr, o Aberdaugleddau, sir Benfro, 1845-1900 = Papers of Rev. William Rhys Watkin, including sermon notes and other papers, 1899-1936; correspondence, 1878-1948, printed Baptist Union of Wales yearbooks containing entries by WRW, 1891-1945; research notes and articles on Bedo Brwynllys, the Rev. E. T. Jones, and Baptist history, 1909-[1945], and notebook of the National Eisteddfod Committee, Llanelli, 1928-1931; and records collected by him, including minutes and accounts of the Welsh Baptist Church, Eldon Street, Moorfields, London, 1846-1905; records of Baptist churches in Carmarthenshire and Glamorgan, 1843-1930; sermon notes and other papers of Richard Davies ('Yr Hen Belican'), 1816-1873; miscellaneous papers and notebooks relating to Welsh Baptists, 1787-1896; and papers of Thomas Jones, mariner, of Milford Haven, Pembrokeshire, 1845-1900.

Holograph copies of articles, etc., by T[homas] Gwynn Jones [professor of Welsh Literature, University College of Wales, Aberystwyth], published in Y Darian, 1919-1926, including a series of articles entitled 'Iwerddon' (18, 25 Medi, 2, 9, 16 Hydref 1919, subsequently published as a booklet (50 pp.) under the same title, Aberdar, 1919); a series of articles entitled 'I Leddfu Gofid' (26 Mai, 9, 16, 23, 30 Mehefin, 7 Gorffennaf 1921, subsequently published as a booklet (63 pp.) under the title Peth Nas Lleddir, Aberdar, 1921); an essay entitled 'Colofnau Mwg' ( 16 Rhagfyr 1926, subsequently published in the author's Beirniadaeth a Myfyrdod, Wrecsam, 1935, pp.119-27); reviews of Saunders Lewis: A School of Welsh Augustans, Wrexham, 1924 (29 Mai 1924), and of Kate Roberts: O Gors y Bryniau. Naw Stori Fer, Wrecsam, 1925 (7 Mai 1925); a letter headed 'Tafodiaith', in reply to a correspondent's observations in Y Darian, 4 Mehefin 1925, on comments by T. Gwynn Jones in his review of O Gors y Bryniau (see above) on the author's use of dialect (11 Mehefin 1925); and adjudications on 'englynion' submitted in a literary competition organised by Y Darian (28 Rhagfyr 1922), on the 'rhieingerddi' and 'myfyrdraethau' submitted for competition at the National Eisteddfod of Wales, 1923 (16 Awst 1923; for the adjudication on the 'rhieingerddi', see also Cofnodion a Chyfansoddiadau Eisteddfod Genedlaethol 1923 . . . Barddoniaeth a Beirniadaethau, pp.95-6), on the chair poems and 'englynion' submitted at the Cardiff and District Welsh Societies Eisteddfod, 1925 (2, 9 Ebrill 1925), and on the short stories submitted in a competition organised by Y Darian, 1925 (26 Tachwedd 1925). Most of these items are listed in A Bibliography of Thomas Gwynn Jones. Reprinted from The Bibliography of Denbighshire, Part 3, Wrexham, 1938. See also the supplement to this work, published in Denbighshire Historical Society Transactions, vol. 5, 1956, pp. 131-49.

Manuscript and typescript notes of lectures, addresses and articles, [c. 1940]-1960, by David James Jones ('Gwenallt') relating to his upbringing and the background to his poetry, Christianity and society, Communism, the decline of religion, the poet and Christianity, hymnology and hymnists, and aspects of poetry and literary appreciation.

Notebook, 1959-1961, of Caradog Prichard, poet and journalist, containing a fragment of a diary, in English, 3 November 1959-26 January 1960 (ff. 3-14 rectos); 'A Scheme For A Daily Newspaper In The Welsh Language' (ff. 16-18 rectos); notes for, and fragmentary draft of, Un Nos Ola Leuad (1961) (ff. 18v, 19-23 rectos, 61v); numerous drafts of poems, mainly of parts of 'Cân yr Hen' from his ode 'Cymru'; and miscellaneous notes and personal memoranda.

Twelve holograph poems by Waldo Williams, [1956] (ff. 1-10), written down from memory with the encouragement of Prof. J. Gwyn Griffiths and Dr Kate Bosse-Griffiths at their flat in 1 Eaton Crescent, Swansea; with the exception of 'Arfau' (ff. 6 verso-7), all the poems appeared in the volume Dail Pren (Llandysul, 1956). Also included are page proofs of the first typesetting of Dail Pren prepared by Gwasg Gomer in June 1956 (ff. 11-103), arranged by the poet with the help of Prof. Griffiths and Dr Bosse-Griffiths and including a few manuscript emendations in the hand of Prof. Griffiths.
The first typesetting differs significantly from the first published version of November 1956, with the poet having omitted twenty of the sixty-three poems and added twenty-three new poems.

A notebook (MS 22861iB) mainly containing pasted-in newspaper cuttings of poems in Welsh by David Morgan ('Cerddwyson', 1862-1935), Merthyr Tudful, composed between 1900 and 1929, with manuscript additions. Items found loose inside the volume have been filed separately (MS 22861iiE); they comprise two pamphlets: the periodical Cenad Hedd for March 1910, which contains an article on Maggie Morgans, the poet's mother, and Lledu'r Gorwelion (Merthyr Tydfil, 1928), being the printed version of Cerddwyson's address to the Congregationalists of the North Glamorgan Association on his retirement as chairman in October 1927; together with two related newspaper cuttings, 1936-1991.

Notebooks, 1946-71, in Welsh, of Kate Davies containing reviews of her published books and lecture notes, 1969, on Castellhywel, Llandysul, in 1906-7, and on the poetry of her father, Daniel Thomas (1866-1942) and David Davies, Penlôn, Gyfeile, Llandysul, beirdd gwlad, along with copies of their poems. Miscellaneous papers found loose inside the volume have been filed separately (MS 23116iiD).

Allbrintiau o bedair ar ddeg o gerddi a gyfansoddwyd gan Iwan Llwyd ar gyfer arddangosfa, 8 Ebrill-30 Medi 2000, yn Llyfrgell Genedlaethol Cymru, i ddathlu chwecanmlwyddiant dechrau gwrthryfel Owain Glyn Dŵr. Fe'u cyhoeddwyd yn Owain Glyn Dŵr 1400-2000 (Llyfrgell Genedlaethol Cymru, Aberystwyth, 2000). Ceir hefyd gywydd 'Teulu Owain Glyndŵr' nas cynhwyswyd yn y gyfrol.