Isabella Jagiellon
Isabella Jagiellon was the oldest child of Polish King Sigismund I the Old and his Italian wife Bona Sforza. In 1539, she married John Zpolya, Voivode of Transylvania and King of Hungary, becoming Queen consort of Hungary. At the time Hungary was contested between Archduke Ferdinand of Austria who wanted to add it to the Habsburg domains , local nobles who wanted to keep Hungary independent , and Sultan Suleiman the Magnificent who saw it as a vassal state of the Ottoman Empire . While Isabellas marriage lasted only a year and a half, it did produce a male heir John Sigismund Zpolya born just two weeks before his fathers death in July 1540. She spent the rest of her life embroiled in succession disputes on behalf of her son. Her husbands death sparked renewed hostilities but Sultan Suleiman established her as a regent of Transylvania on behalf of her infant son. The region developed as a semiindependent buffer state noted for its freedom of religion. Ferdinand, however, never renounc
The married life was short and not happy. 20yearold Isabella had to deal with 52yearold husband who complained of gout and overall ill health. In spring 1540, Zpolya traveled to quell a revolt in Transylvania by Stephen Majlth160 . Isabella stayed in Buda as she was pregnant. Their son John Sigismund Zpolya was born onJuly 1540. Zpolya succeeded in subduing the rebels, but he died onJuly from cerebral hemorrhage.
Source: Wikipedia