The Welsh, and original, name for Guinevere, found in Welsh legend. It is a name that does not appear to have been in use prior to the establishment of the Arthurian cycle.

In one version of the story of Culhwch and Olwen, however, a character named as Gwenhwyfar, who may be the same, is said to have had two servants named Yskyrdaw and Yseudydd, who could run as rapidly as their thoughts, both of whom joined the expedition mounted by Culhwch to locate Olwen.

According to a Welsh Triad, Arthur had three queens of this name, who were the daughters of Cywyrd, Gwythyr, and Gogfran.