The Date clan (or the Idate clan) was a samurai family which designated itself as the Fujiwara no Yamakage line of the Northern House of the Fujiwara clan and prospered in the southern Tohoku region from the Kamakura Period through the Edo Period.
伊達氏（だてうじ／いだてうじ）は、鎌倉時代から江戸時代まで東北地方南部（南東北）を本拠とした一族で、藤原氏の藤原北家山蔭流と称する。