Senyllt, King of Selcovia
(Born c.AD 512)
(Welsh: Senyllt; Latin: Seniltus; English: Senild)

Senyllt was a son of King Cedic of Greater Strathclyde. Upon his father's death, in the early 6th century, the kingdom seems to have been divided between his brother, Tutgual Tutclyd, and himself. Being the elder of the two, Tudwal took the greater portion of Strathclyde, whilst Senyllt appears to have become king of the region around Selkirkshire where the people were known as the Selgovae. Although the name of his kingdom is unknown, for identification purposes, the Latin 'Selcovia,' would seem appropriate. He was succeeded by his son, Nudd Hael.