At the age of five Jadwiga celebrated her ‘sponsalia de futuro’ or ‘provisional marriage’ to Leopold’s son, William.15 He was only a few years older at the time. The two children were bound to one another in a lavish ceremony in Hainburg on 15 June 1378. It was a serious event which meant that the couple could legally consummate their marriage as soon as Jadwiga turned 12 without any need for another church ceremony. They were effectively married.
