Deeds and documents (1668-1882) relating to properties mainly in in co. Flint (Axton, Bistre, Caergwrle, Coleshill, Cwm, Cwm Uwchglan, Diserth, Estyn or Hope, Hawarden, Holywell, Hope, Hope Owen, Huriathicke, Kilken, Kinnerton, Mould, Newmarket, Northop, St Asaph, Shordley, Skeiviog, and Whitford), but also in cos Denbigh (Denbigh, Henllan, Llanrwst and Lleweny), Chester (Chester and Dodleston), Brecknock (Devynnock), Anglesey (Amlwch, Coedana, Llanerchymedd, Llanbadrug, Llanddyfnan, Llanfechell and Llanfihangel Tre'r Beurdd), Montgomery (Berth Lloyd) and Pembroke (Amroth). The main families were Mostyn of Mostyn Hall and Hope of Broughton and Hope.

Minute books, 1895-1971, of the Llandysilio Liberal Association, 1895-1909 and Montgomeryshire Liberal Association, 1920-1970; financial records; 1934-1989; administrative correspondence and papers, 1961-1984; files relating to the Liberal campaign in Montgomeryshire in the parliamentary elections, 1955-1983; constituency papers of Clement Davies, 1945-1962, and Emlyn Hooson, 1967-1979; press cuttings, 1962-1987; bound electoral registers for the parliamentary constituency of Montgomery, 1953-1983; papers relating to the Welsh Liberal Party, 1973-1979, the Montgomery in Europe Group, 1975, Young Liberals, 1970-1980, Liberal Party organization, 1977-1983, Supper Clubs, 1980-1983, Montgomeryshire Liberal Association Annual General Meetings, 1980-1985, Liberal Party Annual Conferences, 1980-1985, and the Welsh Campaign for Fair Votes, 1983-1984; printed materials, 1959-1987; Liberal party materials, 1963-1985; typescript draft policy statements, 1972-1974; Newsletters of the Montgomeryshire Liberal Association, 1978-1984; Association of Liberal Councillors, 1979-1984, and Focus, 1980-1982.

An additional group of records, 1904-1939, were received per Dr David Steeds comprising extensive files of correspondence, the minutes of the Association and its various committees and sub-committees, financial material, press cuttings and printed material. There are also many files deriving from the parliamentary general elections campaigns of the period 1906-29 in Montgomeryshire. There are also papers relating to the North Wales Liberal Federation, 1940-46, and the Liberal Federation of Wales, 1943-45. The records cover the period when David Davies, Llandinam (1880-1944) was the Liberal MP for Montgomeryshire, 1906-29, and the early years of its representation by his successor E. Clement Davies (1884-1962). This group remains uncatalogued.

Abstracts, etc., from Montgomeryshire Plea Rolls and other records, made for D. C. Lloyd-Owen by Ernest Arthur Ebblewhite (1867-1947).

Papers, 1885-[1922x1936], of Ernest Richmond Horsfall Turner, largely of Montgomeryshire interest. They include extracts, notes and draft essays relating to Llanidloes and Montgomeryshire history, including the Chartist movement within that county; addresses prepared for local societies, meetings, etc.; correspondence; and compositions submitted for the Llanidloes Eisteddfod of 1912; together with poetry by John Newton Crowther (Glanceri), Horsfall Turner's father-in-law.

Treatises in Latin; a Greek vocabulary; material relating to the hundreds and parishes of Merioneth, Montgomeryshire and Pembrokeshire; 'the Syren & the hundredes of Engelonde'; rentals of several North Wales manors; an account of a tax paid by North Wales counties in 1701; a transcript of documents of King Alfred; etc.

Papers of Tom Owen, HMI, of Aberystwyth, Cardiganshire, 1898-1966, mainly relating to his career in education, including inspector's reports on schools in Montgomeryshire, 1946-1950; reports on St. David's College, Lampeter, Cardiganshire, 1907-1945; and personal papers, 1898-1966.

Papers of Mary Garbett Edwards, including scrapbooks containing family photographs and letters, [1890]-1973; Montgomeryshire Liberal Party, General Purposes Committee, minute book, 1950-1959; letters, 1929-1983; journals of visits to North America, 1936-1949; notebooks and notes for speeches, [20th century]; radio scripts and related material, 1943-1963; papers relating to Garbett Edwards, including eisteddfod essays and other papers, 1897-[1930s], journal of Canadian visits, 1936-1939, and publications and annual reports of the Mid Wales Industrial Development Association, 1957-1973.

Deeds, 1555-1918, of clients and relating to properties in Cardiganshire, Merionethshire, Montgomeryshire and Radnorshire, including papers of the Penglais estate in the Aberystwyth area, 1555-1918; Aberystwyth borough records, 1759-1813; letters, 1794-1882; papers of John Parry, solicitors, Aberystwyth, including share certificates of the Aberystwyth Gas and Coke Company, 1839; Bwlch Consolidated Lead Mines, 1847; records concerning the Aberystwyth and Tregaron Bank, 1813-1844; miscellaneous papers, [c. 1783]-1932; printed items, [c. 1783]-1867; certificates of shares in the Aberystwyth Public Rooms, 1818-1821, and the Robinson Gold Mining Company, 1903; letters and papers relating to the estate of Roderick Richards, Penglais, [c. 1830]; builders' accounts, 1845; and tithe receipts, 1927-1932.

Clement Davies's papers, [c.1884]-1967, mainly Liberal Party papers, 1928-1962, Clement Davies's political career, 1929-1965, Welsh affairs, 1936-1962, peace movements, 1940-1962, foreign affairs, 1944-1962, constituency papers, 1951-1962, and home affairs, 1953-1963; and papers and correspondence of Jano Clement-Davies, 1873-1969, and papers of Stanley Clement-Davies, 1920-1963.

Deeds, documents and plans, 1455-1895, relating to properties in Anglesey, Caernarfonshire, Denbighshire, Merionethshire and Montgomeryshire; including papers of the Poole family, owners of the Caenest and Pencraig estates in Merionethshire and Anglesey; surveys, [c. 1770] of the Caenest and Pencraig estates; and building leases for properties in the port of Amlwch, [late 18th century].

Genealogical and other notes from various sources, including certified copies of entries in parish registers, etc., mainly relating to persons and places in Montgomeryshire.

Title deeds and other documents, 1608-1794, relating mainly to properties in Montgomeryshire and Shropshire.

Deeds and documents, 1555-1875, relating to properties in the counties of Pembrokeshire, Anglesey, Montgomeryshire; deeds, 1696-1868, of lands in the parishes of Llanfair Dyffryn Clwyd, Llanelidan, Efenechtyd, and Llanfwrog, Denbighshire; and documents, 1735-1868, relating to the Eyarth Estate, Denbighshire.

Papers, 1839-1931, relating to the Naylor family and the Leighton Hall and Brynllywarch estates, comprising accounts, rent schedules, valuations and sale catalogues, together with correspondence and other material relating to the family, and in particular to their activities as high sheriffs for Montgomeryshire.

Additional papers were received in July 2021, this material mainly comprising correspondence and newspaper cuttings, which trace the history of and events within the Naylor family and the Leighton Hall estate from the mid-nineteenth century to the near present day. The material includes a memorandum book, 1848-1856, belonging to John Naylor (1813-1889) of Leighton Hall.

Records, correspondence and notes, 1819-1983, relating to the history of Manafon school.

Transcripts of the titles of Welsh ballads contained in a manuscript at one time [1925] in the possession of Hugh Davies, Lluest, Llangadfan, Montgomeryshire, together with transcripts by Hugh Davies of the titles of books of local Montgomeryshire interest, with notes by the transcriber on the authors and subjects of the ballads and books.

Copi o draethawd a gyflwynwyd ar gyfer gradd MA gan Lona Jones (née Gwilym) yn dwyn y teitl 'Traddodiad barddol Maldwyn yn y ddeunawfed ganrif', Prifysgol Cymru Aberystwyth, 1983.

Records, 1841-1897, of Trefeglwys School Board, 1871-1897; Llangurig School Board, 1874-1898; Poor Law Records of Newtown and Llanidloes Poor Law Union for the parish of Trefeglwys, Montgomeryshire, including: rate books, 1845-1892; Overseer's receipt and payment books, 1849-1872; and Collector's unpaid rates statement books, 1853-1883; and miscellaneous papers, 1879-1897.

Papers of John Sheringham mainly reflecting his research interests, including his research into Montgomeryshire place-names, 1980-1995, medieval Welsh history and laws, 1984-1995, and Breton history, 1988-1989; typescript notes on Welsh law, 1986-1990; typescript drafts of published works, and papers of the Machynlleth and District Civic Society, 1979-1993, and the Aberystwyth and District Civic Society, 1990-1994.

Survey, [1600x1675], relating to Ryston, Mountgom[er]y, Wititree, Tunebert, Stocton, Woderton, Marinton, the church of Churburye, and a warren in the manor of Worthin.