Tillamook, Native North Americans whose language belongs to the Salishan branch of the Algonquian-Wakashan linguistic stock (see Native American languages). In the early 19th cent. they lived on Tillamook Bay and in neighboring river valleys in NW Oregon. They then numbered some 2,200 and were the most powerful tribe on the Oregon coast. By 1849, however, they had been reduced to some 200. Although descendants of the Tillamook still live in Oregon, they are no longer organized as a tribe.