Tillamooks attempted to gain power from spirits, whom they believed were more active and closer to humans in the winter. Shamans renewed their power in January or February by sponsoring a ceremony that included singing a power song and dispensing food and presents to guests. During the course of this five- to fifteen-day ceremony, all other "knowers" (those with spirit powers) sang their songs too. Winter was also the time for relating myth narratives. Mythological characters were particularly important because social status was dependent on one's ability to form a relationship with a mythological personage, a natural feature, or a guardian spirit. Rituals also accompanied the first seasonal consumption of various foods.
Tillamook society was divided into the many free and the few slave people as well a majority of people who had acquired guardian spirits and a minority of those who had not. The elite were wealthy and experts in doctoring, war, and hunting. Women received status from their own guardian spirits or from those of their close relatives. Older women were accorded higher status.
Depending on the particular activity, different people, including shamans, headmen, and warriors, played leadership roles in the numerous small villages. Headmen were particularly skilled orators and negotiators. Most disputes, up to and including murder, were settled by arbitration and involved payment. This was often the case even with people from other villages.
The Tillamooks recognized five types of shamans: healers (men by drawing with the hands and women, by sucking), poison doctors (men with much ritual paraphernalia to send and extract poisons), spirit doctors (men who personally retrieved lost spirits from the spirit world), love doctors (women), and baby diplomats (men who foretold events by conversing with babies).
Women wore large grass, tule rush, or shredded-bark back aprons, small front aprons, and buckskin leggings. Men wore fur or basketry caps, breechclouts, buckskin shirts, and hide pants. Beaver and painted buckskin capes and rabbit, bobcat, or sea otter fur blankets kept people warm in the winter. Footgear included both moccasins and snowshoes. Items such as menstrual pads and diapers were made of cedar bark. Both sexes painted their hair part red and wore ear pendants. Men also wore nose pendants. Women wore decorative tattoos, but men's tattoos served only to measure dentalium.
Winter villages were usually built at the mouths of rivers or streams. They typically consisted of several houses, at least one work-and-menstrual hut, sweat houses, and a graveyard. Rectangular houses, which were occupied by up to four families, were constructed of cedar planks tied together with peeled and steamed spruce roots. Roofs were gabled with overlapping planks. Each had several fires in a center pit and sleeping platforms along the sides. Some houses were built aboveground and some were semisubterranean (with a door in the roof and entry via a ladder). Mat partitions separated families and multiple wives. Floors were covered by ferns and rush mats. Pitch torches or fish head or whale oil lamps provided extra light. Roots were kept in pits beneath the floor.
Salmon and other fish were the staples. Other seafood included sea lions, seals, and shellfish. Women gathered salmonberries, huckleberries, strawberries, camas, ferns, and other plant foods. Men hunted elk, beaver, muskrat, bear, and water-fowl. Many foods were either steamed in earth ovens, stone-boiled in baskets or bowls, or dried on racks. Canoes of several sizes and shapes were used for travel and fishing. They were single-log dugouts, painted black on the outside and red on the inside, and coated with pitch. The Tillamooks were part of a flourishing regional trade. In general, they traded tanned beaver hides, canoes, and baskets to northern Columbia River peoples for abalone shell, dentalia, buffalo hides and buffalo horn dishes, and dried salmon. The Tillamooks bought wapato roots and other items from Columbia River peoples east of the Coastal Range. They traded and intermarried with the Kalapuyas, and they also raided their southern neighbors for slaves, which they sold in the north.
History records the first contact between the Tillamooks and non-Natives as occurring in 1788, although iron knives and smallpox scars told of at least indirect encounters previously. They were also visited by Meriwether Lewis and William Clark. Regular contact with traders began after 1811. Epidemics of malaria, syphilis, smallpox, and other diseases, as well as guns and liquor, diminished the Tillamook population by around 90 percent in the 1830s and greatly reduced the number of their villages.
In 1850, the Donation Land Act opened Tillamook lands for white settlement. The Indians ceded land in an unratified 1851 treaty, and the few surviving Tillamooks either remained in place, officially landless, or were removed to the Siletz or Grand Ronde Reservation. Under the leadership of the peaceful Kilchis, Tillamooks refused to participate in the wars of the 1850s. Awards from the Indian Land Claims Commission in 1958 and 1962 did little to reunite a scattered and unorganized people. Congress officially terminated its relationship with the Tillamooks in 1956.