Duchy of Gniewkowo

The Duchy of Gniewkowo was a district principality and a fiefdom within the Kingdom of Poland during the era of fragmentation that was formed in 1314 from part of the Duchy of Inowrocław. The country was located in the Kuyavia and consisted of Gniewkowo and Słońsk Lands. Its capital was Gniewkowo and other important settlements were Szarlej, Złotoria and Słońsk. It was ruled by Kazimierz III of Gniewkowo and later his son, Władysław the White, from the Piast dynasty. In 1332 the duchy was conquered by the State of the Teutonic Order and was reestablished in 1343. Between 1363 and 1364, the duchy was incorporated into the Kingdom of Poland. Duke of Gniewkowo, Władysław the White, had later briefly re-established the duchy in the rebellion fought between 1373 and 1374 and later between 1375 and 1377, and eventually given up his claims to the land in 1377.