Buahahaha, having a troll for a step-mother xD

But it's a very interesting question. And it took me a great deal of time to answer it. Arthur never knew Ygraine and he should be completely clear of any trauma related to her death. In fact, it really was not a traumatic experience for him because he was a baby. Uther was traumatized and he never spoke to Arthur about Ygraine. Arthur is most likely more curious about Ygraine- he'd like to know what qualities he shared with her- than traumatized over her death. If he is ever to learn about the truth of her death then he'll definitely be angry and horrified. I don't think it haunts him though.

As for Uther's death. He was extremely upset and rightfully so, but I don't think his father's death will haunt him in any way. Uther was going to die at some point anyways and Arthur was going to ascend to the throne. It might have been a shock for him, but I don't think he will be haunted by something as such.

Morgana's betrayal may haunt him until the end, but then again, where was his fault in it? Uther was far more traumatized because he was much more to blame in the situation. It's the same with Agravaine. While Arthur may be terribly distraught over his uncle's betrayal, he is still angrier and will question what he, himself did wrong? But I don't think he will be completely traumatized.

Arthur loves Gwen far too much for her "betrayal" to ever be haunted by what she did. He knows she loves him so unconditionally and he could never lose her anyways. Of course, discovering the enchantment is a different matter entirely, but it would do Gwen far more good than it would do Arthur- who has completely forgiven her. Their love is all encompassing.

So, I had to choose this one. Because Arthur was completely at fault here and he will definitely be haunted by this. His actions at the shrine may have been decreed by Uther but he went through with it. I think it will definitely affect him as King, therefore.

I like the Having a troll for a step-mother idea XD

I think Uther's death and executing women and children.

i share vampyrefey's sentiments

Morgana over Uther ? are you kidding ? WTF ?
losing a father and becoming king earlier would be more traumatic that a friend betraying you
jeez O_O

he sees it as being his fault because he chose to try magic to save Uther and when it went wrong he blamed himself because Uther would never have taken such a risk. Then, on the day after his father's death, Arthur has to become king and start ruling a kingdom. HOW IS THIS IN ANY WAY NOT TRAUMATIC???