- Joseph Jenkins
- Place of Birth: Pontrhydygroes, Cardiganshire
- Dates: 1886-1962
- Dai y Dderwen (1926)
- Robin y Pysgotwr (1926)
- Ianto ac Ystoriàu Eraill (1929)
- Robert Thomas Jenkins
- Place of Birth: Liverpool
- Dates: 1881-1969
- Hanes Cymru yn y Ddeunawfed Ganrif (1928)
- Ffrainc a’i Phobl (1930)
- Yr Apêl at Hanes (1930)
- Ffordd yng Nghymru (1933)
- Hanes Cymru yn y Bedwaredd Ganrif ar Bymtheg (1933)
- Orinda (1943)
- Ffynhonnau Elim (1945)
- A History of the Honourable Society of Cymmrodorion (co-author) (1951)
- Dictionary of Welsh Biography (editor) (1953)
- Casglu Ffyrdd (1956)
- Edrych yn Ôl (1968)
- Y Traethodydd (1970)
- Bobi Jones: See Robert Maynard Jones.
- Elias Henry Jones
- Place of Birth: Aberystwyth, Cardiganshire
- Dates: 1883-1942
- The Road to En-dor (1920)
- Elizabeth Mary Jones (Moelona Jones)
- Place of Birth: Rhydlewis, Cardiganshire
- Dates: 1878-1953
- Dwy Ramant o’r De (1911)
- Teulu Bach Nantoer (1913)
- Cwrs y Lli (1927)
- Alys Morgan (????)
- Elizabeth Watkins Jones
- Place of Birth: Nefyn, Caernarfonshire
- Dates: 1888-1966
- Plaut y Mynachdy (1939)
- Luned Bengoch (1946)
- Y Cwlwm Cel (1947)
- Y Dryslwyn (1947)
- Esyllt (1951)
- Lowri (1951)
- Lois (1955)
- Elwin Jones
- Place of Birth: Cwmaman, Glamorganshire
- Dates: 1923-1982
- The Last Two to Hang (1966)
- Barlow in Charge (1973)
- The Barlow Casebook (1975)
- The Ripper File (1975)
- Death Trials (1981)
- Emyr Jones
- Place of Birth: Waun-fawr, Caernarfonshire
- Dates: 1914-
- Canrify Chwarelwr (1963)
- Bargen Dinorwig (1980)
- Gwaed Gwirion (1965)
- Grym y Lli (1969)
- Erasmus Jones
- Place of Birth: ????
- Dates: 1817-1909
- The Captive Youths of Judah (1856)
- The Adopted Son of the Princess (1870)
- The Welsh in America (1876)
- Llangobaith: The Story of North Wales (1886)
- Gold, Tinsel, and Trash (1890)
- Ernest Charles Jones
- Place of Birth: Berlin, Germany
- Dates: 1819-1868
- The Lass and the Lady (????)
- The Maid of Warsaw (????)
- Women’s Wrongs (????)
- The Painter of Florence (????)
- The Battle Day (1855)
- The Revolt of Hindustan (1857)
- Corayda (1859)
- Geraint Vaughan Jones
- Place of Birth: Llandudno, Caernarfonshire
- Dates: 1819-1868
- Christology and the Myth in the New Testament (1956)
- The Art and the Truth of the Parables (1964)
- Y Fro Dirion (1974)
- Broc Môr (1979)
- Y Ffoaduriaid (1979)
- Yr Hen a’r Ifaine (1983)
- Morwenna (1983)
- Gofeb (1983)
- Gwilym Meredydd Jones
- Place of Birth: Glanyrafon, Flintshire
- Dates: 1920-
- Dawns yr Ysgubau (1965)
- Ochr Arall y Geiniog (1982)
- Gwerth Grôt (1983)
- Yr Onnen Unig (1985)
- Gwyn Jones
- Place of Birth: Blackwood, Monmouthshire
- Dates: 1907-
- Four Icelandic Sagas (1935)
- Richard Savage (1935)
- Times Like These (1936)
- The Nine Days’ Wonder (1937)
- A Garland of Bays (1938)
- The Buttercup Field (1945)
- The Green Island (1946)
- The Still Waters (1948)
- The Flowers Beneath the Scythe (1952)
- The Walk Home (1962)
- Shepherd’s Hey (1953)
- A Prospect of Wales (1948)
- Welsh Legends and Folk Tales (1955)
- The Norse Atlantic Saga (1964)
- A History of the Vikings (1968)
- Kings, Beasts, and Heroes (1972)
- Gwyn Owain Jones
- Place of Birth: Cardiff
- Dates: 1917-
- The Catalyst (1960)
- Personal File (1962)
- Now (1965)
- The Conjuring Show (1981)
- Harri Pritchard Jones
- Place of Birth: Dudley, Worcestershire
- Dates: 1933-
- Troeon (1966)
- Dychwelyd (1972)
- Pobl (1978)
- Meddwl Modern (1982)
- John Gwilym Jones
- Place of Birth: Groeslon, Caernarfonshire
- Dates: 1904-1988
- Y Brodyr (1934)
- Diofal yw Dim (1942)
- Y Dewis (1942)
- Goeden Eirin (1946)
- Lli Mynno’r Gwynta Gwr Llonydd (1958)
- Tad a’r Mab (1963)
- Hanes Rhyw Gymro (1964)
- Pedair Drama (1971)
- Rhyfedd y’n Gwnaed (1976)
- Ac Eto Nid Myfi (1976)
- Yr Adduned (1979)
- Tri Diwrnod ac Angladd (1979)
- Moelona Jones: See Elizabeth Mary Jones.
- Owen Wynne Jones (Glasynys)
- Place of Birth: Rhostryfan, Caernarfonshire
- Dates: 1828-1870
- Dafydd Llwyd neu Ddyddiau Cromwell (1854)
- Fy Oriau Hamddenol (1854)
- Lleuca Llwyd (1858)
- Yr Wyddfa (1877)
- Rhiannon Davies Jones
- Place of Birth: Llanbedr, Merionethshire
- Dates: 1921-
- Fy Hen Lyfr Cownt (1961)
- Lleian Llanllyr (1965)
- Llys Aberffraw (1977)
- Eryr Pengwern (1981)
- Dyddiadur Mari Gwyn (1985)
- Richard Jones
- Place of Birth: Rhydyfelin, Cardiganshire
- Dates: 1926-
- The Age of Wonder (1967)
- The Toy Crusaders (1968)
- A Way Out (1969)
- The Tower Is Everywhere (1971)
- Robert Gerallt Jones
- Place of Birth: Llyn, Caernarfonshire
- Dates: 1934-
- Ymysg y Drain (1959)
- Y Foel Fawr (1960)
- Yn Frawd i’r Eos Druan (1961)
- Cwlwm (1962)
- Nadolig Gwyn (1962)
- Gwared y Gwirion (1966)
- Jamaican Landscape (1969)
- Ansawdd y Seiliau (1972)
- Cysgodion (1972)
- Bardsey (1976)
- Triptych (1977)
- Gwyntyll y Corwynt (1978)
- Cafflogion (1979)
- Pererindota (1979)
- Dyfal Gerddwyr y Maes (1981)
- Robert Lloyd Jones
- Place of Birth: Minffordd, Merionethshire
- Dates: 1878-1962
- Ynys y Trysor (1926)
- Capten (1928)
- Mêt y Mona (1929)
- Ym Môr y De (1936)
- Robert Maynard Jones (Bobi Jones)
- Place of Birth: Cardiff
- Dates: 1929-
- Y Gân Gyntaf (1957)
- Nid yw Dwr yn Plygu (1958)
- I’r Arch (1959)
- Bod yn Wraig (1960)
- Rhwng Taf a Thaf (1960)
- Y tair Rhamant (1960)
- Lenyddiaeth Saesneg yn Addysg Cymru (1961)
- Emile (1963)
- Cyflwyno’r Gymraeg (1964)
- System in Child Language (1964)
- Tyred Allan (1965)
- Man Gwyn (1965)
- Cymraegi Oedolion (1965-1966)
- Y Dynna Ddaeth Adref (1966)
- Yr Wyl Ifori (1967)
- Ci Wrth y Drws (1968)
- Daw’r Pasg i Bawb (1969)
- Highlights in Welsh Literature (1969)
- Podwar Emynydd (1970)
- Allor Wydn (1971)
- Sioc o’r Gofod (1971)
- Traed Prydferth (1973)
- Tafod y Llenor (1974)
- Ysgrifennu Creadigal i Fyfyrwyr Prifysgol (1974)
- Cyfeiriadur i’r Athro Iaith (co-author) (3 vol. (1974-1979)
- Llenyddiaeth Cymru (1975)
- Gwlad Llun (1976)
- Ann Griffiths: y Cyfrinydd Sylweddol (1977)
- Llên Cymru a Chrefydd (1977)
- Pwy Laddodd Miss Wales (1977)
- Thomas Llewelyn Jones
- Place of Birth: Pentrecwrt, Carmarthenshire
- Dates: 1915-
- Trysor Plas y Wernon (1958)
- Trysor y Morladron (1960)
- Y Ffordd Beryglus (1963)
- Penillion y Plant (1965)
- Ymysg Lladron (1965)
- Swn y Malu (1967)
- Dial o’r Diwedd (1968)
- Corn, Pistol, a Chwip (1969)
- Yr Ergyd Farwol (1969)
- Barti Ddu (1973)
- Cerddi Newydd i Blaut o Bob Ded (1973)
- Un Noson Dywyll (1973)
- Y Corff ar y Traeth (1973)
- Cri’r Dylluan (1974)
- Cyfrinach y Lludw (1974)
- Arswyd y Byd (1975)
- Tân ar y Comin (1975)
- Ysbryd Plas Naut Esgob (1976)
- Dirgelwch yr Ogof (1977)
- Lawr ar Lau y Mô4 (1977)
- Tom Parri Jones
- Place of Birth: Anglesey
- Dates: 1905-1980
- Preiddiau Annwn (1946)
- Teisennau Berffro (1958)
- Yn Eisiau, Gwraig (1958)
- Traed Moch (1971)
- Y Ddau Bren (1976)
- Y Felltith (1977)
- Cerddi Malltraeth (1978)
- William Glyn Jones (William Glynne-Jones)
- Place of Birth: Llanelli, Carmarthenshire
- Dates: 1907-1977
- Brecon Adventure (1945)
- Dennis and Co. (1947)
- He Who Had Eaten of the Eagle (1948)
- Farewell Innocence (1950)
- Pennauts on the Main (1950)
- Ride the White Stallion (1950)
- Summer Long Ago (1954)
- Legends of the Welsh Hills (1957)
- The Childhood Land (1960)
- William John Jones
- Place of Birth: Ystradmeurig, Cardiganshire
- Dates: 1928-
- Rhwng y Sêr (1957)
- Ffoi heb ei Erlid (1959)
- Amser i Faddau (1964)
- Y Cleddyf Aur (1971)
- Heledd (1973)
- William Morgan Jones
- Place of Birth: Margam, Glamorganshire
- Dates: 1864-1945
- The Village Lyre (1934)
- Caniadau’r Pentref (1934)
- William Samuel Jones
- Place of Birth: Llanystumdwy, Caernarfonshire
- Dates: 1920-
- Tair Drama Fer (1962)
- Pum Drama Fer (1963)
- Dau Frawd (1965)
- Ty Clap (1965)
- Y Fainc (1967)
- Dinas Barhausa Thair Drama Arall (1968)
- Mae Rhywbeth Bach (1969)
- Dinas (1970)
- Ifas y Tryc (1973)
- Y Toblarôn (1975)
- Dyn Y Munci (1979)
- Y Sul Hwnnw (1981)
- Place of Birth: Pontrhydygroes, Cardiganshire