- GWILYM TWROG - see WILLIAMS, WILLIAM
- GWINNE, ROBERT JOHNS - see GWYNNE, ROBERT JOHNS
- GWINNETT, BUTTON (1735 - 1777), merchant, landowner and politician
- GWRGANT - see JONES, WILLIAM
- GWRNERTH - see STEPHENS, THOMAS
- GWRTHEYRN
- GWRTHEYRN - see ROBERTS, GRIFFITH
- GWRWST - see JONES, Evan
- GWRWST ab BLEDDYN FLAIDD - see JONES, EVAN
- GWYDDERIG - see WILLIAMS, RICHARD
- GWYDDON - see STEPHENS, THOMAS
- GWYDDONWYSON - see STEPHEN, DAVID RHYS
- GWYLFA - see ROBERTS, RICHARD GWYLFA
- GWYLLT Y MYNYDD - see EVANS, WILLIAM HUGH
- GWYN, Dolau-gwyn, Meirionnydd - see WYNN
- GWYN, ANTHONY, landowner - see GWYN, FRANCIS
- GWYN, CHARLES (1582 - 1647) - see BODVEL
- GWYN, EDWARD ap HUGH Bodewryd (d. 1596/7) - see WYNN
- GWYN, EDWARD ap HUW Bodewryd (d. 1596/7) - see WYNN
- GWYN, FRANCIS (1648? - 1734), politician
- GWYN, FRANCIS, landowner - see GWYN, FRANCIS
- GWYN, HUGH (d. 1611), M.P. - see BODFEL
- GWYN, HUGH, sheriff of Caernarfonshire - see BODWRDA
- GWYN, HUW Bodewryd (d. 1652) - see WYNN
- GWYN, JOHN (d. 1574), lawyer, placeman, and educational benefactor
- GWYN, JOHN EDWARD ap HUW GWYN (d. 1614), high sheriff of Anglesey - see WYNN
- GWYN, OWEN, master of S. John's College, Cambridge - see WYNN
- GWYN, OWEN, master of S. John's College, Cambridge - see GWYN, JOHN
- GWYN, OWEN (d. 1633), master of S. John's College, Cambridge - see WYNN
- GWYN, RICHARD (c. 1537 - 1584), Roman Catholic martyr
- GWYN, ROBERT JOHNS - see GWYNNE, ROBERT JOHNS
- GWYNDAF - see DAVIES, GRIFFITH
- GWYNDAF ERYRI - see JONES, RICHARD
- GWYNDAF IEUANC - see JONES, HUGH
- GWYNEDD - see EDWARDS, THOMAS
- GWYNEDDON - see DAVIES, JOHN
- GWYNETH VAUGHAN - see HUGHES, ANNIE HARRIET
- GWYNFARDD BRYCHEINIOG (fl. c. 1180), poet
- GWYNFOR - see JONES, THOMAS OWEN
- GWYNIONYDD - see WILLIAMS, BENJAMIN
- GWYNLLYW (fl. late 5th-early 6th century), saint
- GWYNN, EIRWEN MEIRIONA (1916 - 2007), scientist, educator and author
- GWYNN, HARRI (fl. c. 1627), poet
- GWYNN, HARRI (1913 - 1985), writer and broadcaster
- GWYNN, JOHN - see GWYN, JOHN
- GWYNN, OWEN, master of S. John's College, Cambridge - see WYNN
- GWYNN, OWEN, master of S. John's College, Cambridge - see GWYN, JOHN
- GWYNN, OWEN (d. 1633), master of S. John's College, Cambridge - see WYNN
- GWYNNE family Garth, Maes-llech, Llanlleonfel
- GWYNNE family Llanelwedd,