Archaeological investigations in the Yukon valley have not been well-documented. Evidence from other portions of northern Alaska indicates that people lived in the area as early as 11,000 years before the present. Northern Athabaskan speakers moved into the region by about 1500 BP. One theory proposes that the eruption of the White River Ash about 1900 years ago from Mount Churchill in the St. Elias Mountains displaced people from the region of Kluane Lake into the relatively ash-free Yukon valley.