A prehistoric subculture of the Eskimos that began in Alaska about 900 AD and spread as far as Greenland by 1000 AD. The culture was distributed throughout the northern Arctic from Siberia to Greenland, and ancestral to most of the historic Eskimo cultures of that area. The latest phase in the west dates to c 1300. Thule people lived in circular houses partially dug into the ground and roofed with whalebones, turf, and stone. Tools are mainly bone, ivory, antler, and polished slate rather than chipped stone and they made coarse impressed pottery (later replaced by soapstone vessels). They hunted and fished with harpoon points, used skin-covered boats (open ones = umiaks, closed ones = kayaks), and dog sleds for travel across land and ice. Thule made ornaments of ivory, bone, and stone with simple geometric designs. It was the final Eskimo culture of the Northern Maritime tradition. It either absorbed or supplanted the Dorset Culture of the central and east Arctic. The Thule were the Skraelings discovered by the Vikings in the 10th century AD.