the principal religious specialist of the Baltic Finns, functioning in the tradition of the Finno-Ugric shaman. Operating in a more complex, agricultural society than his more primitive counterparts, such as the Sami noiade, who worked in a hunting and fishing society, the tietäjä-type specialist differed from his predecessor chiefly in the number of roles he mastered, as well as in the degree of specialization exemplified in them.

Nevertheless, as a shamanic specialist, the tietäjä's main task was still to act as the community's first line of defense against hostile supernatural forces, whether they originated in the otherworld or with sorcerers and other evil-minded people. The term tietäjä literally means “knower,” implying that as the specialist he knew more than ordinary humans about the nature of the supernatural world and of techniques for dealing with it. He could be called on to aid in almost any problem that was either not adequately understood or not amenable to correction by ordinary means. He was consulted mostly in matters of illness, but he also served as priest, diviner, judge, name giver, spokesman, and entertainer. Even in the position of healer, there was a great deal of specialization in regard to the tasks and techniques used by individual practitioners. The overall status of the tietäjä was also higher in the agricultural society than that of the shaman in the hunting and fishing milieu because of his additional social influence and political power accruing from his multiple roles. It is this role differentiation, above all, that sets him apart from the more primitive specialist.