Marriage. Traditionally, marriages between members of the same clan or moiety were frowned upon. Historic Hidatsa villages were agamous, as intervillage marriages were Common. Marriages functioned as a bond between both Individuals and kin groups, and occurred by arrangement, purchase, or elopement. Monogamy was rare as polygyny was the prevailing form of marriage. The sororate and levirate also were practiced. Postmarital residence was theoretically matrilocal, but depopulation during the historic period resulted in multi-local residence as households attempted to widen their Strategies for incorporating male and female residents.
Domestic Unit. Traditionally, the domestic unit was the matrilocal extended family, an earthlodge household consisting of a core of matrilineally related women. Since reservation times the domestic unit has been influenced by the nuclear family model, but bilateral extended families are common.
Inheritance. Traditionally, patrilineal and matrilineal Inheritance occurred with the former applying mainly to Medicine bundles.
Socialization. Aboriginally, much of Hidatsa socialization was informal and provided by the matrilineal extended Family. Children were reared permissively into male and female roles. Generosity, self-reliance, and patience were values inculcated by parents. Males during adolescence and young adulthood were taught to be assertive and competitive as preparation for warfare and entrance into age-grade societies. Fasting, ritual self-torture, and mock combat underscored these values. Young girls were taught modesty, diligence, and patience in preparation for adulthood and marriage. Today cooperation, noninterference, kin support, and tribalism are important socialization values.