Traditionally she was a sixth-century Brittonic princess of the ancient kingdom of Gododdin (in what became Lothian) and the mother of Saint Mungo, apostle to the Britons of Strathclyde and founder of the city of Glas Ghu (Glasgow).

[2] Variants include Thenewe, given by the Aberdeen Breviary; Thennow of Adam King's Calendar; and the Welsh Bonedd y Saint calls her Denyw (or Dwynwen).

Alex Woolf has suggested that the character Teneu may have been derived from Danaë, mother of the classical hero Perseus in the Fabulae of Gaius Julius Hyginius.

Owain was disguised as a woman, and after sexually assaulting the naïve princess, he confused her by saying: "Weep not, my sister, for I have not known thee as a man is used to know a virgin.

[7] Miraculously she survived the fall; when discovered alive at the foot of the cliff, Teneu was set adrift in a coracle and travelled across the Firth of Forth to Culross, where she was given shelter at the community of Saint Serf.