Math Mathonwy

Math is about 2300 years old. He was born around 500 BC, when Ireland was beginning to slip out of the Splendor. The Splendor was the time after the Tuatha Dedanan and the exile of the Fomori. The Sidhe lived openly amongst the mortals of Ireland. Math was a human child who was fostered by a Sidhe noble. Math showed incredible talent as a sorcerer, so much that he was trained from an early age. His rival was his foster sister, a half-Sidhe woman who would become known as Morgana La Fae, but back then, she was just Morgana.
Math, however, was Morgana's superior. Everything she learned, he learned just the slightest amount better and faster. This infuriated Morgana. She sought anything that would give her the advantage over Math. That was when she found a hidden, ancient tome. Written by a Fomori mage, it whispered of a being of inifnite power, and great evil. Morgana sought this being through her magic. The Red Death found a foot hold in Tir Na Og once more, through Morgana.
With her new, darker powers, Morgana was able to best Math in a duel of magic which she challenged him to. Surprised by her new skill, Math sought to congratulate his foster sister with a smile and a handshake. Upon touching her, he sensed it. Math, being a human, was able to resist the poisonous charm in Morgana's touch. He fought to save the Sidhe, while she quickly spread corruption through the Splendor. Using the magic of the Sidhe, he trained others to fight the corruption that spread throughout Tir Na Og. Their combined power was able to seal the Sidhe in a realm that was just beyond reach of reality. However, the students of Morgana had become powerful in their own rights, and the students Math took, and Math, fled to the four winds.
Math ended up in England. This would be around 100 AD. Math discovered a young man, of an interesting heritage. He was the child of a nun and an incubus. With a talent for magic that surpassed Math's own, Math began training Merlin.
This is where the waters get very muddied. Morgana came, following Math, to destroy him. Merlin and Math had adopted a kingdom of sorts, known as Camelot. Merlin and Math were often confused in the legends, and Math's kinship to Morgana was placed upon Arthur when Math was removed from the legends. What is known is that Morgana couped Camelot, killing Arthur. Merlin stuck back, and managed to banish Morgan away as well. From there, the combatants are lost to history...
Math, still secretly supporting the remnants of the Seelie Sidhain (pronounced Shee - an), has been guarding Merlin's line ever since Merlin gave his teacher a vision. "You will not live to see the return of the Sidhe, good Math, but it will be your hand that redeems them." Math believes that Merlin's line, the most naturally talented in magic he has ever seen, will be the redeemers of the Sidhe.
2000 years after his geasing of the Sidhe, he can feel the seal crumbling. They are on the verge of returning, in all their fell glory. It has become imperative for Math to train the last of Merlin's line: Amelia.