A Livejounal post from ravenya03
"We know that some years prior to the start of the show, Uther strikes a deal with Nimueh to help magically conceive a son with his barren wife Ygraine. She does so, but the cost is that Ygraine dies in childbirth, as per the rules of magic. To create a life, a life must be taken. Uther (who presumably wouldn’t have cared if the life in question was that of a kitchen drudge or minor manservant) decides to assuage his guilt and take his revenge by eradicating magic-users from the entire kingdom. His greatest triumph is using the last dragonlord to chain the last dragon in his dungeons, where it’s doomed to languish forever in darkness and poor living conditions.
So, what we’re left with is a dragon with a massive vendetta against Uther Pendragon and his entire family. All he desires is to destroy their dynasty – but how to do it? He’s chained and helpless. What he needs is someone to do it for him. A powerful but unwitting pawn.
Enter Merlin."
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