The origin of this name is still today quite uncertain. The theories include: 1) From the Welsh name “esyllt”, meaning “'who is gazed at” or from the Welsh name “esyllt”, meaning “of fair aspect”. 2) From the Germanic name “Ishild / Ishilde” combination of the Old High German “*īsarną” (iron) plus the Ancient Germanic “*hildiz” (battle, fight). 3) From the Germanic name “Iswalde” combination of the Old High German “*īsarną” (iron) plus the Ancient Germanic “*waldaʐ” (ruler, might, mighty one, power, powerful one). There are several characters in the Arthurian story of Tristan and Iseult. The most prominent is Iseult of Ireland, wife of Mark of Cornwall and adulterous lover of Sir Tristan. Her mother, the Queen of Ireland, is also named Iseult. The third is Iseult of the White Hands, the daughter of Hoel of Brittany, sister of Sir Kahedin, and eventual wife of Tristan.
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