The Ahnenerbe (German for "Ancestral Heritage") was a Schutzstaffel pseudo-scientific organization in Nazi Germany between 1935 and 1945. It was established by Heinrich Himmler in July 1935 to promote racial doctrines.
This tag mainly refers to its emblem: A sword inside a knot, surrounded with Runic text on the edges that spell out “DEUTSCHES AHNENERBE". post #1193584 for example