The first sejm to legislate for the whole of Poland was the diet of Piotrkow (1493), summoned by John Albert to grant him subsidies; but the mandates of its deputies were limited to twelve months, and its decrees were to have force for only three years.
During Sigismund's reign, moreover, the Crown recovered many of the prerogatives of which it had been deprived during the reign of his feeble predecessor, Alexander, who, to say nothing of the curtailments of the prerogative, had been forced to accept the statute nihil novi (1505) which gave the sejm and the senate an equal voice with the Crown in all executive matters.
He promised never to declare war or levy troops without the consent of the sejm, undertook to fill all vacancies within a certain time, and released the szlachta from the payment of income-tax, their one remaining fiscal obligation.
At the same time, by the compact of Rastawica, the sejm undertook to allow the Cossacks, partly as wages, partly as compensation, 40,000 (raised by the compact of Kurukow to 60,000) gulden and 170 wagons of cloth per annum.
The sejm of 1766 not only rejected the dissident bill, but repealed all the Czartoryscian reforms and insisted on the retention of the liberum veto as the foundation of the national liberties.