The Duchy of Dobrzyń (Polish:Księstwo dobrzyńskie) was a historical state in Dobrzyń Land. The duchy came to existence when Konrad I of Masovia granted the town of Dobrzyń to his eldest offspring.
History
In his Prussian Crusade, Duke Konrad I of Masovia, in 1228, established the Order of Dobrzyń, whom he vested with the Dobrzyń estates. In May 1392, Vladislaus II of Opole pledged the entire Dobrzyń Land to the Teutonic Knights for 50,000 Hungarian florins.
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