Dietrich von Altenburg

Dietrich von Altenburg was the 19th Grand Master of the Teutonic Knights, serving from 1335 to 1341.

He came from the Thuringian town of Altenburg in the Holy Roman Empire, where his father held the office of a burgrave of the immediate Pleissnerland, which however had long been pawned to the Saxon House of Wettin. Altenburg joined the Order in 1307 and served as Komtur of Ragnit (1320–24) and of Balga (1326–31). In 1331 he was appointed Grand Marshal of the Order, and resumed the Polish–Teutonic War smouldering since 1326. After the Battle of Płowce, the Order conquered the former Duchy of Kuyavia with Dobrzyń Land from the Kingdom of Poland under Władysław I the Elbow-high.

Altenburg was accused before a papal tribunal of alleged crimes committed during the Kuyavian campaign. Nevertheless, the relations with Poland improved upon the accession of King Casimir III the Great in 1333 and the election of well-disposed Pope Benedict XII the next year. At the 1335 Congress of Visegrád, by the agency of King John of Bohemia, an agreement was made, whereafter the Polish king would renounce Pomerelia in favour of the Order and in turn regain Kuyavia and Dobrzyń. The arrangement however met with protest by the Polish szlachta, and a final peace was not achieved until 1343 by the Treaty of Kalisz.

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