The Diploma of the Joannites, or Diploma of the Knights of St. John, was a grant issued in 1247 by King Béla IV of Hungary, to Master Rembald of the Knights Hospitaller. It allowed the Knights to settle in Severin, in what is today Romania, where they could defend the Hungarian borders against Cuman invaders.
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Diploma of the Joannites Wikipedia(Text) CC BY-SA