- PAYNE, FRANCIS GEORGE (1900 - 1992), scholar and literary figure
- PAYNE, HENRY THOMAS (1759 - 1832), cleric and ecclesiastical historian
- PAYNTER, RACHEL - see DAVIES, RACHEL
- PEARCE, EVAN WILLIAM (1870 - 1957), minister (Presb.), and author
- PEARSON, ARTHUR (1897 - 1980), Labour politician
- PEATE, IORWERTH CYFEILIOG (1901 - 1982), Curator of the Welsh Folk Museum, 1948-1971, scholar and poet
- PECOCK, REGINALD (c. 1390 - c. 1461), bishop
- PEDR ALAW - see EDWARDS, PETER
- PEDR FARDD - see JONES, PETER
- PEDR HIR - see WILLIAMS, PETER
- PEDROG - see WILLIAMS, JOHN OWEN
- PEIRIANYDD GWYNEDD - see DAVIES, JOHN
- PEMBROKE, Earl of - see TUDOR, JASPER
- PEMBROKE, Earl of - see HERBERT, WILLIAM
- PEMBROKE, Earl of - see HERBERT, WILLIAM
- PEMBROKE, Earls of - see HERBERT
- PEMBROKE, Earls of - see MARSHAL
- PENCERDD CEREDIGION - see EDWARDS, EDWARD
- PENCERDD GWALIA - see THOMAS, JOHN
- PENCERDD GWYNEDD - see ROBERTS, JOHN HENRY
- PENCERDD GWYNFRYN - see CARRINGTON, THOMAS
- PENCERDD LLYFNWY - see OWEN, RICHARD GRIFFITH
- PENCERDD MAELOR - see DAVIES, HUGH
- PENCERDD MYNWY - see GRIFFITH, MORGAN WILLIAM
- PENCERDD Y DE - see WILLIAMS, ZEPHANIAH
- PENCERDDES MORGANNWG - see DAVIES, CLARA NOVELLO
- PENCERDDES TAWE - see PHILLIPS, DAVID RHYS
- PENFRO - see MORGAN, WILLIAM JOHN
- PENNANT family Penrhyn, Llandygâi
- PENNANT, THOMAS (1726 - 1798), naturalist, antiquary, traveller
- PENNAR, ANDREAS MEIRION (1944 - 2010), poet and scholar
- PENNY, ANNE (fl. 1729-1780), author
- PENRHYN, Barons - see PENNANT
- PENRHYS, Baron DAVIES of - see DAVIES, GWILYM ELFED
- PENRI, - see PENRY,
- PENROSE, LLEWELLIN - see WILLIAMS, LLEWELLIN
- PENRY, DAVID (1660? - 1721?)
- PENRY, JOHN (1563 - 1593), Puritan author
- PENRY, JOHN (1854 - 1883), missionary under the L.M.S.
- PENSON, RICHARD KYRKE (1815? - 1885), architect
- PERKINS, WILLIAM (fl. 1745-1776), Independent minister
- PERRI, HENRY (1560/1 - 1617) Maes Glas (Greenfield)
- PERROT family Haroldston,
- PERROT family Haroldston,
- PERROT, JAMES (1571 - 1637), politician - see PERROT
- PERROT, JOHN (1528 - 1592), statesman - see PERROT
- PERROT, THOMAS - see PERROTT, THOMAS
- PERROT, THOMAS (1553 - 1594), politician - see PERROT
- PERROTT, THOMAS (d. 1733), Presbyterian minister, and academy tutor
- PERRY, STANLEY HOWARD HEDLEY (1911 - 1995), professor of theology