In the final years of the Ho'rradin incursion, an unlikely alliance was formed between the Thelléndomiri Elves,
the Dwarves of Stonehall, the Men of the Lowlands, and a contingent of Mages of the Darkan University. After throwing back the Ho'rradin from the Lowlands, and claiming back the Northern section of Hamaglen Pass - the Dwarves went to work erecting a Keep from which the allied forces might hold back the invading hordes. Hamaglen Keep was constructed from stone of the Dwarves own mines, and much of the work on its walls was accomplished even as the battle for the pass continued around them.
When the Keep was complete, the forces of Elkhòren were able to use it as an outpost from which to muster further pushes south, and eventually captured the land up to the neck of the pass – where they erected a secondary wall to protect them from the Desert folk and their Orcish allies.