Patron saint of Wales, 520(?)–589(?), known for his asceticism and for his promotion of hard manual labour. Most information about his life dates from the Latin biography (c.1090) by Rhigyfarch (or Rhygyfarch; anglicized Ricemarch), although Dewi Sant is cited in the Catalogue of Irish Saints (c.900–1000) and Armes Prydein [Prophecy of Britain] (c.930). Rhigyfarch's account may be partisan, as he was the son of Bishop Sulien of Saint David's, Dyfed (until 1974, Pembrokeshire); at that time this centre of Welsh Christianity was resisting domination by Canterbury and the Normans.
Born of a princely family at Vetus Rubus, Ceredigion (Hen Fynyw, Dyfed, formerly Cardiganshire), Dewi took holy orders as a young man and later studied under the Welsh Saint Paulinus on an island, perhaps Llanddeusant on Anglesey. Much is written of his travels, which may have included Jerusalem. On pilgrimage in south Wales and the west of England, he founded twelve monasteries, most notably Glastonbury. The healing waters at Bath, although known to the Romans, are attributed to Dewi. After defeating an Irish chieftain named Boia, he settled at Glyn Rhosyn [L Vallis Rosina; also Mynyw or Menevia] in the far south-west corner of Dyfed, now called Saint David's. His community lived a life of extreme austerity. No cattle were allowed to assist the monks in the tilling of the earth. As they ate no meat and drank only water, Dewi's monks were known as the ‘watermen’. Outsiders had to wait ten days at the gate before entry. Dewi is also described as having denounced the Pelagian heresy. His best-known miracle was preaching at the synod of Llanddewibrefi, where the ground rose beneath him so that all could see and hear him. In art he is represented as standing on a mound with a white dove on his shoulder.
The feast-day of Dewi Sant, 1 March, is a Welsh holiday, a time for patriotic and cultural celebration since the 18th century; it was a day for religious celebration until the Reformation. 1 March was also formerly a day for Welshmen to wear leeks on their person, as noted by Shakespeare in Henry V (1592). The Latin life of Dewi Sant appears in Vitae sanctorum britaniae et genealiogiae, ed. A. W. Wade-Evans (Cardiff, 1944); the Welsh life, Buched Dewi, was edited by D. Simon Evans (Cardiff, 1959); also The Welsh Life of St. David, ed. D. Simon Evans (Cardiff, 1988). See also Ernest Rhys, The Life of Saint David (Tregynon, 1927); TEILO.