User blog comment:OneofthePendragon94/Does someone know what happened to Morgana's mother Vivienne?/@comment-4650675-20130101204713

Here's my theory...

Vivienne was a creature of magic like Morgana and Morgause. So I would say she was killed during the Great Purge....although it would be cruel from Uther's part to murder his daughter's mother in cold blood, I would actually expect it from him-he did not spare druid children, why should he have spared a high priestess? So, I think he killed her, and so Morgana grew up with Gorlois, her husband and presumed father of Morgana.

This would also explain as to why Morgana was sent to Camelot after Gorlois' death, when Uther failed to send reinforcements. If Vivienne was alive, she would probably take Morgana to the Isle of the Blessed and train her like Morgause, or keep her with her in the House of de Bois. Instead, Uther took her in Camelot, so I would say both Vivienne and Gorlois were dead by then. Finally, since Morgana has never spoken of her mother, I think it is safe to assume she never met her.

I too think that the whole Vivienne/Uther thing was lazy writing and only happened so that Morgana has a reason to chase after the throne for 3 consecutive seasons. Why? Because they had Uther betray his best friend, first of all. Secondly, there's every chance that he also betrayed Ygraine. Thirdly, the whole Morgana/Arthur thing that was going on in front of his eyes during season 1. I think it should have never happened or, if it had to, then have Morgana and Arthur have a common mother, Ygraine, like in the legends.