Grong-Haap ruled much of the eastern Moonsea region from -981 DR through -350 DR.
Ironfang Keep was again occupied in -981 DR when Haask, a monstrous greathorn minotaur (Monster Manual IV), declared himself priest-king and claimed the basalt fortress as the capitol of his burgeoning new kingdom, Grong-Haap. Over the next six-hundred years Grong-Haap slowly expanded to cover the modern-day wastes of Thar, the eastern Moonsea, and northern highlands of the Vast. With only an occasional clash with the elves of Cormanthyr or the orcs of Vastar, the minotaur kingdom enjoyed a level of civilization not common among their kind. Then in the late winter months of the Year of Craven Words (-350 DR), a goblinoid horde one-hundred-thousand strong marched against Grong-Haap from the Tortured Lands in the icy north.
Issuing an utterance in a tongue not spoken on Toril since the Days of Thunder, Haask summoned forth an elder manifestation of absolute evil and sick malevolence. Hargut of the Gray Pestilence surveyed the battlefield before turning his undying gaze upon the priest-king. Speaking a powerful recitation of command, Haask then ordered the Gray Pestilence to scatter the invaders and defend the keep. Tens of thousands died that day before the walls of Ironfang Keep, their flesh fed into Hargut’s voracious maw and their souls consigned to an eternity in the Barrens of Doom and Despair.
By dusk the battle was all but won and Haask returned triumphantly to the keep to feast and rest. Inside, the priest-king was stunned to discover two grim looking humans sitting nonchalantly upon his giant-crafted throne. Before Haask could react, a third assassin appeared behind the priest-king, driving a simple iron blade through his back and into his heart. As his life energy pumped into the enchanted dagger, Haask’s form began to shift revealing his true nature as a batrachi-doppelganger. The mysterious trio later exited the keep heading upriver toward the Glacier of the White Wyrm and beyond. Grong-Haap soon collapsed, and for a time Ironfang Keep again fell out of memory.