After the death of Casimir IV Jagiellon (1492), the personal union between the Kingdom of Poland and the Grand Duchy of Lithuania was broken.
The failed invasion of Moldavia in 1497 complicated Poland's internal situation, and strengthened the position of the magnates.
At the same time, Lithuania was attacked by Ivan III of Russia, and in 1499 both nations signed the Union of Kraków and Vilnius, which revived the Polish-Lithuanian alliance.
Starostas did not cooperate with senators, and during the 1504 Sejm, which took place in Piotrków Trybunalski, Jan Łaski initiated attack on the powerful Lesser Poland magnates.
As a result, the nobility managed to regain their position, and during the 1505 Sejm in Radom, the Nihil novi act was introduced, which voided the Privilege of Mielnik.