Three Tusk Clan was a Bizogot tribe of mammoth herders that lived very close to the Glacier. They were officially part of the Raumsdalian Empire though they, like any other Bizogots, scorned the southerners as soft.
Due to their closeness to the Glacier, they were first to notice the Gap and their jart or chief, Trasamund, was the one who reported this development to the Emperor of Raumsdalia, Sighvat II. The latter asked the chieftain to go on a expedition to the lands south of the glacier.
When Trasamund returned and informed the clan that an invasion from the Rulers was imminent, the members of clan just heard out, more interested that the Rulers rode mammoths, rather than preparing for the invasion. Therefore, they were caught unprepared when the Rulers did attack and were decimated. Only 25 or so survived to take vengeance on the Rulers.