Dun-Issout, Esordes, Esorduns, Essondun, Essouduns
A castle in King Claudas’s lands, formerly called simply Dun, but renamed in honor of Issout, its castellan.
Sommer states that the castle Dun was renamed Esordes or Esorduns after its new owner Essent (Issout).
Source
Vulgate Lancelot | 1215-1230