Reichsbund der Kinderreichen (RDK or RdK), Reich's Union of Large Families or literally: Reich's League of those wealthy in children, was one of the most important pronatalist groups founded in Germany after World War I. To qualify as a member of this league a family should have at least four children. Widows were also admitted.
The German Large Family League was forcefully nazified after the Nazi takeover of power in 1933. As such its goal became the preservation and promotion of the German hereditarily healthy Aryan family ("Erhaltung und Förderung der deutschen, erbgesunden, arischen Familie").