The Thule were the ancestors of all modern Canadian Inuit. They arrived at Alaska in around the year 500 and Nunavut, Canada in 1000 and a subgroup moved east to Greenland by the 13th century. The links between the Thule and the Inuit are biological, cultural, and linguistic. The Thule subsisted both on marine and terrestrial animals. They replaced the Dorset culture, which, however, did not become extinct until 1902, when whalers brought disease to the last Dorset settlement on Southampton Island (the Sadlermiut).
The Thule winter settlements usually had one to four houses with around ten people. Some major settlements may have had more than a dozen, although not all were inhabited at the same time by the fifty residents. Their houses were made of whalebones from summer hunts. Other structures include kill sites, caches, and tent encampments.
Some Thule migrated southward, in the "Second Expansion" or "Second Phase". By the thirteenth or fourteenth century, the Thule had occupied an area currently inhabited by Central Eskimo. Contacts with Europeans began and the people were henceforward known as the Eskimo and, later, Inuit.
The Thule period was brought to light by the work of Therkel Mathiassen, a Danish archaeologist who undertook the archeological studies during his travels with Knud Rasmussen on the Fifth Thule Expedition, 1921 to 1924; in so doing he made one of the most radical and significant finds in Arctic archeology.
It is estimated that the Thulepeople, traveling from northern Alaska along the Arctic coast and through the high Arctic islands, reached northwest Greenland around 1100 A.D. Moving south, they came in contact with Viking settlers on the southwest coast of Greenland.
The Thulepeople camped in skin tents during the summer, like their Dorset ancestors, and almost certainly adapted from the Dorsetpeople the practice of building snowhouses for temporary winter quarters, as snowhouses were not part of the Alaskan way of life.