 The leading Hungarian and Polish lords confirmed Louis's promise of Mary's and Sigismund's marriage on 14April 1375.Mary's older sister, Catherine, who had been betrothed to Louis of France, died in late 1378.Louis the Great confirmed his earlier promise of Mary's and Sigismund's marriage to Sigismund's brother, Wenceslaus, King of the Romans, in Zólyom (now Zvolen in Slovakia) in 1379.