Materiana is said to have been a princess of the 5th century, the eldest of three daughters of King Vortimer the Blessed,[2] who, after her father's death, ruled over Gwent with her husband Prince Ynyr.

Traditions of the saint were recorded by William Worcestre in 1478: he states that her tomb was venerated at Minster and that her feast day was 9 April.

[5] There are two memorials which portray St Materiana: a statue in the chancel and a stained glass window in the nave.

The Cornish historian Charles Thomas proposed that the Norman church of Tintagel and its dedication to St Materiana were due to the patronage of William de Bottreaux, lord of Boscastle rather than the Earl of Cornwall.

[7] The parish church at Trawsfynydd is dedicated to a St Madryn, Princess of Gwent, who is usually identified with Materiana.