Archmage Gauldur was a powerful wizard during the dawning days of the First Era. Wise and just, he was well-known in the courts of King Harald and the jarls of Skyrim, and his aid and counsel were sought by man and mer alike. He was murdered by his sons, though it was also speculated that King Harald, jealous of his power, gave the order.
Gauldur's three sons fled into the wilds of the Reach, pursued by a company of Harald's best warriors and the Lord Geirmund, the king's personal battlemage.
Once the brothers had been apprehended and killed, King Harald ordered every record of their murders destroyed, and Gauldur's name and deeds were struck from the rolls of history.