- DERFEL, ROBERT JONES (1824 - 1905), poet and socialist
- DEVEREUX family Lamphey, Ystrad Ffin, Vaynor, Nantariba, Pencoyd,
- DEVONALD, JOHN (1863 - 1936), musician
- DEWI ab IAGO - see DAVIES, JAMES
- DEWI AFAN - see MICHAEL, DAVID
- DEWI ap DIDYMUS - see THOMAS, DAFYDD
- DEWI ap IAGO - see DAVIES, JAMES
- DEWI ARFON - see JONES, DAVID HUGH
- DEWI BREFI - see ROWLAND, DAVID
- DEWI DAWEL - see EVANS, DAVID
- DEWI DINORWIG - see PRICE, DAVID
- DEWI DYWYLL - see JONES, DAVID
- DEWI EINION - see DAVIES, DAVID LLOYD
- DEWI ELFED - see JONES, DAVID BEVAN
- DEWI EMLYN - see DAVIES, DAVID
- DEWI EMRYS - see JAMES, DAVID EMRYS
- DEWI FARDD - see JONES, DAVID
- DEWI GLAN PERYDDON - see DAVIES, DAVID LLOYD
- DEWI HARAN - see EVANS, DAVID
- DEWI HAVHESP - see ROBERTS, DAVID
- DEWI HEFIN - see THOMAS, DAVID
- DEWI HELI - see WILLIAMS
- DEWI HIRADDUG - see EVANS, DAVID DELTA
- DEWI MAI o FEIRION - see ROBERTS, DAVID JOHN
- DEWI MEDI - see JONES, DAVID
- DEWI MOELWYN - see PARRY, DAVID
- DEWI MÔN - see ROWLANDS, DAVID
- DEWI NANTBRÂN - see POWELL, DAVID
- DEWI o DDYFED - see JAMES, DAVID
- DEWI o GEREDIGION - see SAMUEL, DAVID
- DEWI OGWEN - see ROBERTS, DAVID
- DEWI SILIN - see RICHARDS, THOMAS
- DEWI TEIFI - see MORGAN, DEWI
- DEWI WYLLT - see JONES, DAVID
- DEWI WYN o EIFION - see OWEN, DAVID
- DEWI WYN o ESSYLLT - see DAVIES, THOMAS ESSILE
- DEWI Saint - see Saint DAVID
- DIC ABERDARON - see JONES, RICHARD ROBERT
- DIC DYWYLL - see WILLIAMS, RICHARD
- DIC PENDERYN - see LEWIS, RICHARD
- DIC TRYFAN - see WILLIAMS, RICHARD HUGHES
- DIC Y DAWNS - see ABRAHAM, RICHARD
- DILLWYN family
- DILLWYN VENABLES-LLEWELYN, Llysdinam Newbridge-on-Wye - see DILLWYN
- DILLWYN, ELIZABETH AMY (1845 - 1935), novelist, industrialist and feminist campaigner
- DILLWYN-LLEWELYN, Llysdinam Newbridge-on-Wye - see DILLWYN
- DINELY, THOMAS (d. 1695), traveller
- DINGLEY, THOMAS - see DINELEY, THOMAS
- DINORBEN, 1st Baron - see HUGHES, HUGH ROBERT
- DINORBEN, 2nd Baron - see HUGHES, HUGH ROBERT