Thassad II of Hammerfell died and Hammerfell plunged into civil war between The Crowns and The Forebears. The Crowns led by Prince A'Tor won victory after victory, but the Forebears sensed their imminent defeat and became allies with the Septim Empire, allowing the Emperor to bring his forces to conquer Hammerfell. The Empire's forces were too much for the Crowns to handle, and they were defeated again and again. Prince A'Tor, sensing the way the wind was blowing, decided to retreat to the capital Stros M'Kai.
Knowing that Hammerfell's sovereignty is at stake, the Crowns forces matches the might of the Empire. They meet them at the harbor of Stros M'Kai for the final battle. The fighting is fierce, and Lord Amiel Richton, having seen the prince's victories at sea before, decides to bring his last resource to the port: the dragon, Nafalilargus, proud jewel of the Imperial crown. A'Tor commands his archers to ready their weapons, but is struck down himself by Richton's assassin. Paled by a poisoned arrow. A'Tor's wizard attempted to save the prince, but the dragon ended his magic, and the Crowns hope for victory, in a single fiery breath.
With the defeat of the Crowns, Hammerfell was incorporated into the Empire as a province and Admiral Richton was made the Provisional Governor of Stros M'Kai. Nafaalilargus was then put under the command of Lord Amiel Richton. He was then assigned to guard the soul gem of Prince A'tor, in the treasuries beneath the island's palace. The dragon was slain in 2E 864 by Cyrus, who then stole back the soul gem. His death weakened the Imperial presence on the island considerably. However, due to the nature of dragons, Nafaalilargus isn't truly dead and could be raised again.