Orcgate Wars

The Orcgate Wars, which began in -1076 DR, were originally a magical experiment that quickly escalated into a war of devastating proportions across the Old Empires.

History
In -1081 DR, the theurgist adept Thayd, last apprentice of the Imaskari wizards, opened a fateful portal to a brutal world dominated by empires of fanatically religious orcs. After inciting the wizards of Mulhorand and Unther into rebellion, he was executed, leaving no one in Faerûn with knowledge of the existence of the portal. For five years, the portal remained dormant until the orcs began pouring through, eventually laying siege to both Mulhorand and Unther for six years.

More fanatical than those of the north, these invading gray orcs and their clerics had developed amazingly powerful and deadly spells; the most potent of magics being their ability to directly call down avatars of their deities. Avatars of the gods of Mulhorand and Unther also dwelt on Faerûn, but weakened after the oppression under the Imaskari empire, were ill-prepared to defend against the orc hordes.

The orc invasion began in -1076 DR in the lands that later would become Thay, forcing the Mulhorandi to recruit mercenaries to help them quench the orc hordes, among them the warriors of the tribes of Nar, Rashemi and Sossrim. The war took a decisive turning point in the Battle of the Gods, when most of the gods of the Mulhorandi and Untheric pantheons were killed.

Despite their initial victories, the orc armies and their deities were heavily weakened, eventually being routed by the remnants of the Mulhorandi and Untheric pantheons after a rally in -1069 DR.

Aftermath
So complete was the destruction of the orc horde that the gray orcs in the region were never able to fully recover from their losses.

After returning to their homelands, the surviving mercenaries founded a series of kingdoms that eventually gave rise to the nations of Damara, Rashemi and Raumathar.