The Ahnenpaß (literally, "ancestor pass") documented the Aryan lineage of people "of German blood" in Nazi Germany. It was one of the forms of the Aryan certificate (Ariernachweis) and issued by the "Reich Association of Marriage Registrars in Germany" (Reichsverband der Standesbeamten in Deutschland e. V.). The investigation for lineage was not obligatory, as it was a major undertaking to research the original documents for birth and marriage. Many Nazi followers had already begun to research their lineage even before law required it (soon after the NSDAP took power on 30 January 1933).