Papers of Colin A. Gresham, [1524]-1988, including personal papers, 1929-1988; research papers, comprising notes prepared for books and articles, transcripts and photocopies of documents, correspondence with institutions and individuals, and papers concerning the affairs of learned societies and bodies, and offprints of papers by other authors sent to Colin Gresham; and literary papers, including plays and radio scripts, short stories and essays, and drafts of an unpublished autobiography; and miscellaneous papers.

Research and original papers acquired by D. Rhys Phillips, mainly towards a history of the vale of Neath, 1622-1897, including extracts from the letter-books of Alfred Fox of the Neath Abbey Coal Co., 1820-1858, and accounts of the Vale of Neath Railway, 1850-1862; and material towards a history of Swansea, 1622-1814. Papers relating to Nonconformity, 1657-1921, music and hymn books, 1820-1933, Neath Abbey Coal Co., 1865-1874, dialect words, place names, tribannau Morgannwg, poetry, proverbs and folklore, 1896-1948. Correspondence, 1855-1951.

Minute books relating to various Cambridge University societies, Llanelli Committee of Social Service for the Unemployed, Llanelli Park Lodge, Borough Road Chapel, London, etc., 1870-1933; undergraduate notes on history, English literature, Latin, and psychology, and miscellaneous papers relating to history and politics including 'Baronial opposition to Edward II', 1918; papers relating to Monmouthshire archives, 1937-1955; 'The Welsh assize roll 1277-1284: assize roll no. 1147', 1940; reports and preliminary reports, notes etc., on archives acquired by or to be acquired by NLW, 1941-1945; notes, drafts, proofs etc., of articles for the National Library of Wales Journal and items relating to archives in NLW, 1944; papers relating to the Committee on Welsh Calendar Customs, 1944-1947; papers relating to his post as lecturer in palaeography and diplomatic in the University of Cambridge, 1945-1947, and as reader in the same in the University of Durham, 1948-1962, including lectures notes; reports and notes on Welsh Church Commission documents to be deposited in NLW and items on Welsh church history, 1944-1963; episcopal and chapter records of the Welsh dioceses, including notes, drafts and proofs for 'Episcopal acts... Welsh dioceses 1066-1272' (2 vols, 1946 and 1948), and vol. III (Bangor and St Asaph) which was never published; papers as honorary editor of the Journal of the Historical Society of the Church in Wales, 1946-1952; papers relating to Giraldus Cambrensis; notes, photostats, transcripts and typescript of 'Professions of obedience to Canterbury c. 793-1420', proposed to be published by the Camden Society, 1947; miscellaneous papers on history and archives; 'Welsh and Marcher cases coram rege 1272-1307'; papers relating to indexing records at PRO, including transcripts and extracts from documents; notes for reports on the Exchequer records in the PRO; summaries and extracts from Assize Rolls; papers used in the preparation of 'Records of the court of augmentations relating to Wales and Monmouthshire', 1954, and 'The cartae antiquae rolls 11-20', 1960, and the unpublished 'Cartae antiquae rolls 21-30'; typescript and proof articles for 'Studies presented to Sir Hilary Jenkinson', 1957, together with correspondence between contributors and printers; papers relating to the Severn fisheries dispute and the seignory of Gower, 1957-1962; papers used in cataloguing the records of Guernsey, 1959-1969, and in the preparation of 'Catalogue of manuscripts in the library of the honourable society of the Inner Temple', 1972; miscellaneous papers relating to the history of Wales, 1908-1945; film script entitled 'The Black Prince'; diaries, 1946-1971; curricula vitae and papers relating to his personal life and career together with political articles by Prof. Curt Wachtel; photocopies of documents, personal photographs, plaster casts of seals etc.; papers received from Canon E. T. Davies, 1853-1940; uncatalogued correspondence bundles arranged by year, 1909-1971. Copies of his Welsh revolts of Edward II (Llanelli, 1912) and Medieval Northumberland (Llanelli, 1918), journals and offprints; documents relating to the manor of Swavesey, Cambridgeshire, 1623-1833; documents relating to Monmouthshire, 1616-late 19th century; miscellaneous documents relating to England and Wales, 1458-1848; papers and correspondence of Nathan Laski (1863-1941), Harold J. Laski, Professor of Political Science, University of London (1893-1950), Neville J. Laski, Q.C. (1890-1969), John L. Paton, High Master of Manchester Grammar School (1863-1946), Thomas F. Tout, Professor of History, Manchester University (1855-1929), and others including an autographed album.

Research papers of R. F. Treharne and some later items, 1924-1974, mainly comprising notes, manuscript and typescript drafts, and proofs, of articles, books and lectures, together with related correspondence, all relating to mediaeval history, particularly the baronial reforms; together with a manuscript dissertation on Walter de Cantilupe, Bishop of Worcester, 1924, by Ellen Roberts, later Mrs Treharne.

Papurau Bob Owen yn cynnwys traethodau eisteddfodol, 1910-1941; beirniadaethau ar draethodau eisteddfodol, 1916-1949; crynodebau o bregethau a glywodd, 1895-1927; teipysgrifau rhaglenni radio yr oedd ynghlwm wrthynt, 1936-1957; gohebiaeth, 1908-1961, yn cynnwys llythyrau Dr Thomas Richards, 1923-1960; dyddiaduron, 1905-1961; papurau personol, 1898-1961; papurau teuluol, 1900-1923; copïau a drafftiau o ddarlithoedd, erthyglau a thraethodau, 1906-1950; nodiadau ac adysgrifau helaeth ganddo o farddoniaeth Gymraeg, ewyllysiau a mynegeion ewyllysiau, cartiau achau ac achresi, cofrestri plwyf ac adysgrifau'r esgob, dyddiaduron, llythyrau, almanaciau, cofnodion llys, yn ymwneud yn bennaf â siroedd Caernarfon a Meirionnydd, a chofiannau, [20 gan., ½ cyntaf]; nodiadau ar anghydffurfiaeth yng Ngogledd Cymru, plwyfi siroedd Meirionnydd a Chaernarfon, llongau a morwyr o Gymru a Chymry Llundain, [20 gan., ½ cyntaf]; nodiadau pwysig ar ymfudo o Gymru, yn enwedig i'r Unol Daleithiau, [20 gan., ½ cyntaf]; copïau teipysgrif o gofnodion corfforaethau yn cynnwys Parc Cenedlaethol Eryri a Chyngor Sir Feirionnydd, 1922-1962; cofnodion gwreiddiol a ddaeth i feddiant Bob Owen, yn bennaf cofnodion Chwarel Parc a Chroesor, sir Feirionnydd, yn cynnwys cyfrifon a chofnodion, 1891-1941, a chofnodion ysgolion ac ysgolion Sul, 1861-1957; a thorion ac adysgrifau o amrywiol gyfnodolion Cymreig, 1816-1965. = Papers of Bob Owen including eisteddfod essays, 1910-1941; adjudications of eisteddfod essays, 1916-1949; summaries of sermons heard by him, 1895-1927; typescripts of radio programmes involving him, 1936-1957; correspondence, 1908-1961, including letters from Dr Thomas Richards, 1923-1960; diaries, 1905-1961; personal papers, 1898-1961; family papers, 1900-1923; copies and drafts of lectures, articles and monographs, 1906-1950; extensive notes and transcripts by Bob Owen of Welsh poetry, wills and indexes of wills, pedigrees and genealogies, parish registers and bishops' transcripts, diaries, letters, almanacs, court records, mainly relating to Caernarfonshire and Merionethshire, and biographies, [20 cent, first ½]; notes on nonconformists in North Wales, Merionethshire and Caernarvonshire parishes, Welsh ships and sailors and the London Welsh, [20 cent, first ½]; important notes on emigration from Wales, especially to the United States, [20 cent, first ½]; typescript records of bodies including Snowdonia National Park and Merioneth County Council, 1922-1962; original records acquired by Bob Owen, mainly records of Parc and Croesor Quarry, Merionethshire, including accounts and minutes, 1891-1941, and school and Sunday School records, 1861-1957; and cuttings and transcripts from various Welsh periodicals, 1816-1965.