Poppo von Osterna was the ninth Grand Master of the Teutonic Knights, serving from 1252-56 or 1257. Poppo hailed from a family with rich knightly traditions which resided in Osternohe, just outside Nuremberg in Franconia. He joined the Teutonic Order in 1228 and was one of the first friars to settle in Prussia. In 1233, Poppo took part in localisation of the town of Kulm (Chełmno). Wikipedia
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