The first "free election" (Polish: "wolna elekcja") of a king took place in <answer>1492</answer>. (To be sure, some earlier Polish kings had been elected with help from bodies such as that which put Casimir II on the throne, thereby setting a precedent for free elections.) Only senators voted in the <answer>1492</answer> free election, which was won by John I Albert. For the duration of the Jagiellonian Dynasty, only members of that royal family were considered for election; later, there would be no restrictions on the choice of candidates.
When did the first free election take place?
1492