Name Jan Jani | Died 1461 | |
 | ||
Jan z Jani (Joannes de Janie in Medieval Latin, Jan von der Jane in German) (1400–1461) - of the Clan of Ostoja was the first Polish Duke of Pomerelia (from 1454 to 1461) and one of the leaders of the Prussian Confederation, serving as a commander in the Thirteen Years' War (1454–66). He was also the Lord of Regality of Tczew, Nowe County and Kiszewskie, Lord of Starogard Gdański, Rabelnaw, Robaw, Pancze, Wonental, Szwarczenwalt, Weisenwalt, Moealwalt, Landesende, Turze, and Swierczyn in Pomerelia, and Lord of Gniew.
Jan z Jani's origin was from a Dutch noble family that entered the Clan of Ostoja through marriage with the sister of Mikołaj Szarlejski, who was part of the Clan of Ostoja and Duke of Inowrocław and Kujawy, Lord of Bydgoszcz, and member of the Prussian Confederation. Together with Szarlejski, Jan z Jani raised army units in Pomarania during Thirteen Years' War (1454–66) and the conflict with Teutonic Knights. He also cooperated with another member of the Clan of Ostoja, Stibor of Poniec, Lord of Regality of Greater Poland and the renowned diplomat in order to raise funds to attack Malbork, the headquarters of the Teutonic Knights.
Jan z Jani and his family were owners of the property of Świerczyn that in year 1447 belonged to Jenchen de Świerczyn. This line of the family took their name from Świerczyn and called themselves the Ostoja Świerczynski. A local legend speaks of the mighty knight Jan z Jani who designed a new coat of arms and called it the Ostoja.