Casimir the Great, the last Polish ruler from the Piast dynasty, died on 5 November 1370. His death and the end of the dynasty opened the possibility of starting a dynamic process which, after 16 years, finally led to the election of Władysław Jagiełło to the Polish throne. Before that, however, Louis I of Hungary, by virtue of earlier agreements, took over power in Poland. He did not have a male descendant, just two daughters, Maria and Jadwiga. Placing a woman on the Polish throne would be a precedent, the realisation of which must have had its price. That price was the privilege of Koszyce.
By the document of 17 September 1374, King Louis granted the noblemen in the whole kingdom a privilege, under which knights were released from the obligation to pay tribute, except for an annual fee of two Groschen (about 10% of the income of the average nobleman’s estate at that time) from a field (about 25 ha). Moreover, under the new law noblemen were guaranteed full compensation for their participation and losses incurred in a foreign expedition, the construction of new castles, either at the expense of the sovereign or with co-financing from local knights, if they agreed to the tax, the costs of the monarch’s stay in the estate were to be covered by himself, there was also an obligation that new officials would be recruited from amongst the inhabitants of the Kingdom.
Such privileges were nothing special in Europe at that time. Social layers and their parliaments were careful to ensure that sovereigns, when implementing their policies, did not deprive their subjects of their last money. In the Kingdom of Poland, the law of King Louis became one of the foundations for the development of parliamentarianism. Even before the times of the privilege, knights enjoyed much freedom, as they were obliged not by a fief relationship but by knightly law. Noblemen’s ownership was full, not based on the mechanism of feudal contract according to the Western European model. However, from 1374, the position of a knight towards a monarch became even more meaningful. Every time the king needed additional financing, he had to ask the noblemen to enact new taxes. Ruling without the consent of the subjects became very difficult and the way to transform a knight into a citizen was opened.