The Reclamation of the Holds

Thogrim Bronzebeard, the King of the Winter Dwarves led a campaign to reclaim the Dwarven Holds that were all lost during the Age of Dragons. It didn't go well.

After losing many of their ancestral homes in the mountains during the Age of Dragons, the two dwarven factions set off on a campaign to reclaim the holds from whatever opportunistic monsters had taken advantage of their emptiness. After months of brutal battles, the first hold to be reclaimed was the mighty city of Winterforge in the north, home to the Winter Dwarves. After losing many to the fighting, and seeing an opportunity to rebuild from their new keep, King Thogrum Bronzehammer ended the campaign, choosing instead to ignite the forges lest he lose all of his people to the clearly fraught campaign.

The Summer dwarves, former inhabitants of the canyons of the Eastern Continent did not take this well, and have since held a strong grudge against their northern cousins, choosing to work in the cities of men rather than the forges of their traitor-kin.