In 2E 862, High King Thassad II was resisting Imperial invasion. He eventually dies, thrusting the Crowns, who wanted to continue to resist Imperial rule and keep things the same, and the Forebears, who wanted to accept Imperial rule, into civil war. The Crowns are lead by Prince A'tor, heir to Thassad. They continue to win over the Forebears and Imperials, but Dram, a famous Dunmer assassin, picks him off at the island of Stros M'Kai. Lord Richton, the man who beat A'tor at the battle, is then made ruler over Hammerfell, as appointed by Tiber Septim.
In 2E 864, Cyrus the Restless, a Redguard mercenary, and a group called the Restless League incite insurrection in the province; they defeat the Imperial fleet there and repel the ground forces, and Cyrus eventually confronts Lord Richton on a Dwemer Dirigible. Richton cheats and beats him, but the weapon Cyrus is weilding, the Soulsword of A'tor, gains a will of its own and defeats Richton, forcing Tiber Septim to sue for peace in the province.
On a side note, the events involving Cyrus, http://www.imperial-library.info/obscure_text/viveccyrus.shtml, make him an incarnation of the HoonDing, the god that "makes the way" for the Redguard people.
edit: I screwed a date up.