Before the last war against the Teutonic Order. Sejm in Piotrków 1519.

This sejm was convened on 7 December 1518 to begin on 2 February 1519 in Piotrków. The pre-sejm sejmiks were held in January of 1519. The proceedings were not started until 9 February 1519 and were totally dominated by the external threats: escalating conflicts with Teutonic Order and Muscovy, but also by an unsure situation at the southeast border. The sejm finished proceedings on 17 March 1519.

See: M. Biskup, „Wojna Pruska” czyli wojna Poski z zakonem krzyżackim z lat 1519-1521: u źródeł sekularyzacji Prus Krzyżackich [“Prussian war”, that is the 1519-21 war between Poland and the Teutonic Order, origins for secularization of the State of the Teutonic Order], Cz. 2, Olsztyn 1991. Ustawodawstwo zob. Volumina Constitutionum, T. 1, cz. 1, Design and layout prepared by S. Grodziski, I. Dwornicka, W. Uruszczak, Warszawa 1996, s. 306-322.