Outland was created when Draenor became the focus of an attack, via the Dark Portal, of an Alliance expedition aiming to end the orcish threat to Azeroth once and for all. In the midst of the ensuing battle the Elder Shaman Ner’zhul attempted to allow the remaining orcs on Draenor to escape to other worlds by opening other dimensional portals; however the presence of so many portals tore the planet apart, leaving only torn fragments of the former world floating in the Nether, and the barely-habitable remnants were renamed Outland. Most life on Draenor was wiped out in the explosion, although a number of orcs, ogres and some of the few remaining draenei survived. After the explosion, a Pit Lord named Magtheridon rallied the surviving orcs and took control of Outland. Using the remaining Dimensional Gates, he drew demons from the Twisting Nether to aid him.
The night elf demon Illidan Stormrage and many of the Naga and blood elves fled to Outland and succeeded in defeating Magtheridon and conquering the wasteland. After their defeat in Northrend at the hands of Prince Arthas, who used Frostmourne against Illidan, they returned and established permanent settlements there.
Most draenei that remained in Outland have become horribly mutated, and bear only a passing resemblance to their former selves.
Since then, both the forces of the Light and the Shadow have realized Outland’s usefulness. It can serve as a launching pad for the invasions of the Burning Legion, or as the staging ground to the forces who fight against the Legion. In response, both the naaru and the Legion have sent their agents to secure the world for their own purposes.
Now, the Alliance and the Horde must battle the forces of the maddened Illidan and the murderous followers of the Legion to safeguard Azeroth from Kil’jaeden’s Burning Crusade.
Druids have magically replanted some locations on the central landmass of Outland that were formerly desolate, describing the areas as “Green Havens“, such as Sylvanaar in Blade’s Edge Mountains and Cenarion Thicket in Terokkar Forest. The main base of the Cenarion Circle‘s expedition is from Cenarion Refuge in Zangarmarsh.