I've been working on my campaign's Hyborean region lately. I've used the FR accessory FR14 - The Great Glacier quite a lot and I thought I'd share a bit and see what everyone thought. As for the placement of this region, I've tentatively put it northwest of Norwold. I don't have it completely nailed down, but I do like it on Brun as it makes it more accessible to my PCs. Anyway, here is the timeline to AC 1000. This is hardly canon - it's taken from FR14 with a few changes to fit it into Mystara. Enjoy!
HYBOREAN TIMELINE
BC 4500: Beastmen - reincarnated souls of evil beings - are discovered in the upper Borean Valley. These beastmen are wild, chaotic creatures which do not breed true; whelps may have some or none of the traits of their parents, and may be a different size and appearance.
BC 3500: Priests of Blackmoor demand the extermination of the "unnatural" beastmen in the Borean Valley, and promote holy wars to hunt down and destroy those creatures.
BC 3200: The Blackmoor crusades drive the beastmen farther north to the frozen reaches of Hyborea. Arctic breeds of beastmen appear.
BC 3000: The Great Rain of Fire. The Blackmoor explosion tilts the planet's axis so that Hyborea is no longer at the north pole.
BC 2925: The Hyborean glaciers begin to slowly recede and move further north towards the new north pole and the "new" Hyborea.
BC 2500: Dwarves and gnomes move north as the continental ice sheet recedes. One clan of dwarves refuses to participate in a dwarven war party preparing to raid peaceful settlements in the Known World's Northern Reaches. Convicted as traitors, the clan is exiled to Hyborea. The clan begins a year-long trek to an area they call Novularond; all but four die along the way. The survivors are the forebears of a new race of arctic dwarves called the Innugaakalikurit (EE-nu-GA-ka-LEE-ku-rit).
BC 2400: The land of old Hyborea is now warming up; the beastmen migrate out of the area. Some gather at Urzud while others move up into the Hyborean Reaches and beyond into the dark lands to the north.
BC 2098: Antalian hunters skilled in winter survival migrate to search for new species of game in Hyborea. Shortly thereafter, a tirichik ambushes the party and kills the leader.
The survivors panic and become lost, inadvertently moving deeper into Hyborea. Eventually, they reach the shores of an inland sea they eventually call the Lugalpgotak Sea. They renounce their faith in the Immortals, whom they hold responsible for their misfortune. Permanent settlements are established, and the hunters become the precursors of the Ulutiuns (EE-oo-LOO-shee-uns).
BC 1812: Descendants of the hunters expand north from their lands now called Alpuk, discovering the Glacier of Ulutiu near the Uppuk River. Carved in the glacier are mysterious and extensive writings, some of which the hunters manage to translate. Ulutiu is revealed to be the author of the writings, and supposedly the being responsible for the creation for the glacier itself.
Some of the hunters are so impressed with this discovery that they declare themselves disciples of Ulutiu, who they presume to be an Immortal. The group decides to migrate further north and establish their own settlements dedicated to the worship of Ulutiu; these become the forebears of the Nakulutiun tribes. The remaining hunters return to their homes in Alpuk, thereafter calling themselves Iulutiuns.
BC 1800: The Immortal Kagyar transforms the dwarvish race and places them in Rockhome and the Northern Reaches. The arctic dwarves in Hyborea he leaves alone as they seem to be surviving better than the other outer world dwarves.
BC 1636: Lured by the abundance of caribou, an Iulutiun faction moves to Angalpuk. The faction are the first of the nomadic Angulutiuns.
BC 1500: Elsewhere in the world, the Nithian culture climbs to its greatness. No contact is made with Hyborea.
BC 1413: In the wake of a particularly harsh winter, several Iulutiun settlements unite to wage war on their Angulutiun neighbours in Angalpuk, coveting the sizeable Angulutiun caribou herds. The raid triggers the fifty-year Keryjek Wars, named for the mountain range in which most of the fighting occurred.
BC 1363: The Keryjek Wars end with a treaty between the Iulutiun and Angulutiun leaders. To encourage communication and promote good will, the leaders inaugurate the first koatulit, where guests are exchanged for a week-long festival of games and banquets. Koatulit have been held every year since; as a result, there have been few serious conflicts between the Iulutiuns and the Angulutiuns.
BC 1351: Iulutiun representatives from the settlement of Gronne attempt to establish formal relations with the Innugaakalikurit dwarves in Novularond by inviting them to participate in the koatulit. The Innugaakalikurit decline, but the invitation marks the beginning of a long and cordial relationship between the Innugaakalikurit and the Ulutiuns.
BC 1210: The Year of the Great Flood. An unusually warm summer causes the waters of the Nakalpgotak and Lugalpgotak Seas to rise and engulf Ulutiun villages near the shore line. Hundreds of Ulutiuns drown when their villages are washed away.
BC 1048: A party of Innugaakalikurit discovers a Blackmoorian device on a high peak in Novularond. The Innugaakalikurit disassemble the device and take the parts home with them. A day later, an enraged group of frost giants tracks them down and demands the return of the weapon. The Innugaakalikurit refuse. The frost giants respond by attacking and destroying an Innugaakalikurit village.
To avoid an all-out war, the elders of Gronne intervene, volunteering to negotiate a settlement. The Gronne elders ultimately find the Innugaakalikurit guilty of theft; the frost giants are awarded custody of the dwarven thieves. The frost giants make slaves of the prisoners; descendants of the of the prisoners remain enslaved today. The Blackmoor device was ruined beyond all hope of repair when the dwarves disassembled it.
BC 662: Rumbles from the depths of the Olyniak Crevasse attract the attention of curious Nakulutiuns. The Nakulutiuns inadvertently awaken a slumbering monster in the crevasse, described by a survivor as "a grotesque blend of a tirichik and a white dragon, as large as a mountain, with fangs of gold and wings of ice." The monster devours dozens of shrieking Nakulutiuns before returning to the crevasse. The monster, named Ufloq by the Nakulutiuns, has not been seen since.
AC 0: Elsewhere in the world, the first Emperor of Thyatis is crowned.
AC 10: Treasure hunters from Thyatis enter Angalpuk, bringing with them a rare disease that doesn't affect the hunters, but proves deadly to both Angulutiuns and caribou. Hundreds of Angulutiuns and caribou succumb to the sickness, before the carriers are isolated and exiled to the Ibelgrak Valley in the southeastern corner of Angalpuk. A few caribou and Angalpuk in the Ibelgrak Valley are believed to still carry the dormant disease.
AC 588: All traces of the old Hyborean glacier has finally melted.
AC 691: A contingent of evil wizards from the Alphatia employ their powerful magic to construct a castle of ice at the base of Mount Okk, one of the tallest peaks of the Lugsaas Chain. The wizards use the castle as a base to develop a new type of cold-based magic with which they plan to conquer the Flaemish lands. They amass a sizeable cache of gems and precious metals for use in their magical research, stored in a labyrinth beneath the castle, guarded by a small army of magically-generated ice monsters.
AC 698: A massive earthquake rocks the Lugsaas Chain. A fissure opens near the base of Mount Okk, swallowing the ice castle of the Alphatian wizards. An avalanche dumps tons of snow and ice on the fissure, burying the castle and its occupants. The wizards are presumed dead.
AC 868: Azlum Swith, one of Mystara's greatest explorers, begins his twenty-year trek through the Hyborean Reaches, culminating in the writing of Blood and Ice: Survival in Hyborea, the definitive arctic survival guide.
AC 980: Sharra Swith, the great-great-great-granddaughter of Azlum Swith, decides to continue her grandfather's work, planning to focus Volume Two of Blood and Ice on the treacherous Nakvaligach region, an area of Hyborea that Azlum was unable to fully explore. Travelling alone, Sharra enters Hyborea about 100 miles northeast of the Frozen Forest. She is never heard from again.
Azlum (who has used several potions of longevity and is still exploring the
far reaches of Mystara) is currently planning another expedition to Hyborea to
search for clues. In light of the returned Karameikan Polar Expedition, believes
his granddaughter might have entered the Hollow World via the north polar
opening.