Morgause (Morgawse)

   Geoffrey of Monmouth in his Historia states that Arthur had a sister Anna who was daughter of Uther. Uther gave Anna in marriage for political reasons to the Northern ruler, Loth of Lodonesia (As Arthur later names him ruler of the Lothians) who commanded the army during Uther's illness and while Arthur matured. (There is some confusion on Geoffrey's part, indicating that a sister of Arthur was also married to Budicius, king of the Armorican Britons, who is listed as father of Hoel. As King Hoel is afterward called cousin, I suspect that she was an aunt, sister of Uther and Ambrosius, who stayed in Armorica when the brothers returned to Britain to reclaim their lands.)
   Anna and Loth had two sons, Gawain and Mordred. By these straight forward comparisons, we can see that Anna from the early accounts is Queen Morgawse of Malory.

Morgawse in Malory's le Morte