Fenris Isle is a large island located in the center of Lordamere Lake and it is generally considered to be a part of Silverpine Forest. Together with the Dawning Isles, they form a broken circle of dry land in the lake. It is currently controlled by the Alliance and the Bloodfang pack who are based at Fenris Keep, and they also maintain their control over Shadowfang Keep.
When the undead Scourge took the land, Fenris Isle was abandoned, all of its inhabitants either fled or were murdered. The island was then occupied by the Rot Hide gnolls, who took the keep as their base of operations. The Rot Hides were led by their treacherous master, Thule Ravenclaw, who took complete control of the island and the nearby Decrepit Ferry. They were eventually defeated.
Some time later, the island was taken over by Hillsbrad Refugees who had made their way here from ruined Southshore and Hillsbrad Fields. These survivors of the Forsaken attacks would live in peace but for a moment, as agents of the Forsaken along with Agatha entered the island and began killing them and raising them into the undead. Darius Crowley and Ivar Bloodfang made the Refugee Leadership an offer they couldn't refuse, either die and join the ranks of the undead - or drink his blood and become worgen, becoming immune to undeath, and continue to fight for the Alliance. Most of them ultimately chose vengeance, temporarily driving away the attacking Forsaken and Horde forces, with several hundred Hillsbrad Refugees becoming Hillsbrad Worgen shortly afterwards, and Ivar and the others having apparently made their blood offering to every surviving human in Lordaeron. The newly reinvigorated worgen openly fought with Forsaken forces in Silverpine Forest, attempting to assist the Gilneans in retaking their homeland and the rest of Lordaeron for the Alliance.
During the Fourth War, after the Battle for Lordaeron, Fenris Keep was overtaken by Deathstalker Hayward, who was later defeated by Alliance champions, with Ivar Bloodfang and the rest of the Bloodfang Pack reclaiming the isle for themselves in the process. The Bloodfang were distracted by Horde forces along the Misty Shore, while Forsaken refugees escaped from Tirisfal Glades across Lordamere Lake.
Mathias Shaw noted his main contact in Silverpine Forest as Ivar Bloodfang, stating that the packleader was his contact within Shadowfang Keep. The pack has apparently successfully reclaimed it, along with maintaining their control over Fenris Isle, and have taken most of the artifacts within Shadowfang Keep to Fenris Keep to be guarded closely.
In the RPG
Lordamere Lake contains an island called Fenris Isle on which once held a great fortress known as Fenris Keep, but the structure has sunk into the bog and is now mostly submerged and covered with mud and scum.
- Fenris Keep and Fenris Isle are likely a reference to Fenrisulfr Fenrir, the horrific wolf who was the brother of the world serpent and the goddess of hell. Fenrir was bound by the Norse gods on a remote island in a massive lake inaccessible to mortals or giants. He is the eternal foe of Odin the Allfather.
- One Arcane Observatory might have been located in the Fenris Isle archipelago.
- Although the worgen have only recently come to control the island and its keep, it was called Fenris Isle even during the Second War.
- This formation might have been once the rip of an ancient volcano, long since eroded down by the elements.