- GWGON ap MEURIG (bu farw 871), brenin Ceredigion, a'r olaf o linach Ceredig
- GWGON BRYDYDD (fl. c. 1240), bardd
- GWILI - gweler JENKINS, JOHN GWILI
- GWILYM ab ELIS - gweler ELLIS, WILLIAM
- GWILYM ab IOAN - gweler WILLIAMS, WILLIAM
- GWILYM ALAW - gweler OWEN, WILLIAM
- GWILYM AMAN - gweler JONES, GWILYM RICHARD
- GWILYM ap GRUFFYDD (c. 1370 - 1430) - gweler GRIFFITH
- GWILYM ap IEUAN HEN (fl. c. 1440-80), bardd
- GWILYM ap IOAN - gweler WILLIAMS, WILLIAM
- GWILYM ap IORWERTH - gweler WILLIAMS, WILLIAM
- GWILYM ap SEFNYN (fl. c. 1440), bardd
- GWILYM CALEDFFRWD - gweler GRIFFITH, WILLIAM
- GWILYM CALEDFRYN - gweler WILLIAMS, WILLIAM
- GWILYM CALLESTR - gweler EDWARDS, WILLIAM
- GWILYM CANOLDREF - gweler MIDLETON, WILLIAM
- GWILYM CARADOG - gweler EVANS, DAVID
- GWILYM COWLYD - gweler ROBERTS, WILLIAM JOHN
- GWILYM CYFEILIOG - gweler WILLIAMS, WILLIAM
- GWILYM DDU GLAN HAFREN - gweler OWEN, WILLIAM
- GWILYM DDU O ARFON (fl. c. 1280-1320), bardd
- GWILYM DDU O ARFON - gweler WILLIAMS, WILLIAM
- GWILYM DEUDRAETH - gweler EDWARDS, WILLIAM THOMAS
- GWILYM ELIAN - gweler COSLETT, COSLETT
- GWILYM ERYRI - gweler ROBERTS, WILLIAM
- GWILYM GARW-DYLE - gweler HARRI, WILLIAM
- GWILYM GELLI-DEG - gweler MORGAN, WILLIAM
- GWILYM GLAN LLWCHWR - gweler OWEN, WILLIAM
- GWILYM GWALSTAWD IEITHOEDD - gweler THOMAS, WILLIAM
- GWILYM GWENFFRWD - gweler THOMAS, WILLIAM THEOPHILUS
- GWILYM GWENT - gweler WILLIAMS, WILLIAM AUBREY
- GWILYM GWYN (fl. diwedd y 15g.), bardd
- GWILYM HIRAETHOG - gweler REES, WILLIAM
- GWILYM LLEYN - gweler ROWLANDS, WILLIAM
- GWILYM MAI - gweler THOMAS, WILLIAM
- GWILYM MARLES - gweler THOMAS, WILLIAM
- GWILYM MEUDWY - gweler OWEN, WILLIAM
- GWILYM MORGANNWG - gweler WILLIAMS, THOMAS
- GWILYM MORGANWG - gweler WILLIAMS, THOMAS
- GWILYM MYRDDIN - gweler JONES, WILLIAM
- GWILYM O FEIRION - gweler PUGHE, WILLIAM OWEN
- GWILYM PADARN - gweler EDWARDS, WILLIAM
- GWILYM PENNANT - gweler POWELL, WILLIAM
- GWILYM PERIS - gweler WILLIAMS, WILLIAM
- GWILYM RHONDDA - gweler THOMAS, WILLIAM PHILLIP
- GWILYM RYFEL (fl. 12fed ganrif), bardd
- GWILYM TEILO - gweler DAVIES, WILLIAM
- GWILYM TEW (fl. c. 1470), un o feirdd Morgannwg
- GWILYM TEW - gweler MOSES, WILLIAM
- GWILYM TEW O LAN TÂF - gweler MOSES, WILLIAM