Duchy of Płock

The Duchy of Płock was a feudal district duchy in Masovia, centered on the Płock Land. Its capital was Płock. It existed in the High Middle Ages era, from 1275 to 1294, from 1310 to 1351, and from 1381 to 1462.

History
The country was established in 1275, in the partition of the Duchy of Masovia, with duke Bolesław II of Masovia becoming its ruler. After his death, the duchy was unified with the Duchy of Czersk, forming the Duchy of Masovia, on 24 June 1294. The state was again reestablished in 1310, in the partition of Duchy of Masovia. In 1351, it was partitioned between the Kingdom of Poland, Duchy of Czersk, and Duchy of Warsaw. It was again reestablished in June 1381, in the partition of the Duchy of Masovia, with duke Siemowit IV as its first leader. It existed until 1462, when it got partitioned between the Kingdom of Poland, and the Duchy of Warsaw.