Members of the House of Karen were of notable rank in the administrative structure of the Sassanian empire in multiple periods of its four-century-long history.

[6] This figure has been identified with Hystaspes, a member of the Achaemenid royal family who fought under Darius III during Alexander the Great's invasion of Persia.

[7] However, the first verified reference to the Karenas was during the Arsacid Empire, specifically as one of the feudal houses affiliated with the Parthian court.

In 783, however, under Vandad Hormozd and allied with the Bavands, the Karenas proclaimed independence and refused to continue to pay tribute.

Other notable members of the family include Maziar, the grandson of Vandad Hormozd, whose devotion to Zoroastrianism and defiance of the Arabs brought him great fame.