the Proto-Eskimo-Aleut language was spoken, which broke up around 2000 BC. Differentiation of the two branches is thought to have happened in Alaska because of the linguistic diversity found in the Eskimo languages of Alaska relative to the entire geographic area where Eskimo languages are spoken (eastward through Canada to Greenland). After the split between the two branches, their development is thought to have occurred in relative isolation.

Evidence suggests a culture associated