Oberon

Overthrew Queen Mab, imprisoned her somewhere, became ruler of the Third Race
Angered by the scorn & arrogance with which his Wife & people treated mortals;
995: Banished the entire Third Race from Avalon, to live in the mortal world
1996: Returned, battled the Avalon Clan, was defeated, impressed by their morals;
Allowed them to stay on the Island as his Honor Guard, started the Gathering
Attempted to kidnap Alexander Xanatos, eventually allowed him to remain