"Theodor Schieffer (11 June 1910 in Bad Godesberg – 9 April 1992 in Bad Godesberg) was a German historian. He was professor of medieval history at the University of Mainz, then at the University of Cologne, and since 1952 he was president of the Association for Middle Rhine Church History. He is the author of Winfrid-Bonifatius und die christliche Grundlegung Europas, the authoritative biography of Saint Boniface." - (en.wikipedia.org 18.10.2020)
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