Margen
In 1573, the nobility of Poland and Lithuania did something revolutionary: they elected their king by vote. The winner was Henry of Valois, brother of the King of France, who before being crowned had to sign articles that seriously limited his power. A monarchy with terms and conditions — almost an employment contract.
Henry arrived in Kraków in 1574 and the job failed to charm him: he spoke no Polish, found the winters unbearable and the court alien. A few months in, news arrived that changed everything: his brother Charles IX had died and the French throne was vacant.
He didn't negotiate, didn't give notice, didn't abdicate. One June night he slipped out of Wawel Castle in secret and rode for the border with a small entourage. Polish nobles chased him to the edge of the kingdom without catching him.
He reigned in France as Henry III. Poland took a while to officially accept his resignation.