The Baysen family was part of a larger
Flemish family which came in the 13th century from
Lübeck or its vicinity. They named themselves after their possession,
Basien (Bażyny) near
Wormditt (Orneta) in
Ermland (Warmia). Initially, he was employed by the
Teutonic Knights and their
Grand Masters, among them
Konrad von Erlichshausen and
Ludwig von Erlichshausen. He was one of the order's native lay associates. In service of the Grand Masters, Jan traveled on diplomatic missions to
England,
Denmark and
Portugal in the years 1419–1422. According to legend he was knighted by the
King of Portugal for his military service against the
Moors during the
Reconquista, which was reflected in a modification to his family's
coat of arms. After
Michael Küchmeister resigned as head of the order, Bażyński also terminated his service with the knights. He was also one of the ambassadors of Grandmaster Paul von Rusdorf, who appointed him to a member of a secret council. He was a leader of the gathering of
Prussian nobility in 1435 which was dissastified with the rule of the Teutonic Knights. He was also a member of the
Lizard Union, an organization of Prussian nobles and knights who sought the incorporation of Prussia into the Kingdom of Poland. As the
Standard-bearer of
Ostróda (Osterode) he took part in the founding of the Prussian Confederation, He was a member of the Secret Committee of the Confederation and took a public stance against attacks made against the organization by the papal legate and the new Grand Master of the Order. He was the head of the delegation which came from
Toruń (Thorn) to
Kraków in February 1454, which asked the King of Poland
Casimir IV Jagiellon to reincorporate Prussian lands into the Polish kingdom. Consequently, he led the uprising of the Prussian Estates against the Knights. In 1454, during the
Thirteen Years' War, in which the cities of the Prussian Confederation financed Polish military expenses, he was made governor of Royal Prussia by the King of Poland, which after the war became a part of the
Polish–Lithuanian Commonwealth. As the governor his residence was in
Elbląg. In 1457 and 1459 he commanded the defense of Malbork against attacks by the Teutonic Knights, who also unsuccessfully tried to assassinate him. In 1454 he was made the
starosta of
Sztum (Shtum) and in 1456 of
Tolkmicko (Tolkemikt). He died at
Marienburg Castle (Malbork Castle) and was buried at Elbląg. He was succeeded as governor of Royal Prussia by his brother
Ścibor Bażyński (Tiburcius/Stibor von Baysen). ==Legacy==