Her father wanted the inheritor of his throne to be among his immediate family, so he made it clear to the nobles that one of his daughters would be crowned after him. This made his daughters extremely attractive to neighboring royal bachelors, who would gain a throne along with a bride. The Duke of Austria even proposed marriage between his son William and Jadwiga when she was not even a year old. Louis agreed to the Duke's offer, affirmed on 15 June 1378; the marriage would take place when they both came of age. As part of the arrangement, Jadwiga moved to Austria to learn their language and customs.
Jadwiga's oldest sister, Catherine, died in 1378, and Louis had his nobles swear an oath of loyalty to the middle child, Mary. The plan was for Mary to be the heir to Poland and Jadwiga (with William of Austria) the heir to Hungary.
Louis died on 10 September 1382, leaving a widow and two young daughters. Mary was crowned King of Hungary five days later, but her mother arranged that she would run the country on behalf of the 12-year-old king instead of Mary's intended husband, Sigismund of Luxembourg (then only 14).
The nobles of Poland decided they did not like the idea of outsiders ruling Poland, but they could not easily overturn the marriage promise between Mary and Sigismund (who was likely to be the next Holy Roman Emperor, after his father). The queen mother, Elizabeth, released the nobles from the oath of loyalty to Mary (and Sigismund). Elizabeth offered to have Jadwiga named the next heir to the throne of Poland. The assembled nobles liked this plan, and they wanted her to marry a Polish prince, Siemovit IV, Duke of Masovia.
This looked like a good plan, but in the background another plan was forming. The House of Tęczyński was an influential Polish family, and for reasons of their own started negotiations with Jogaila, the Grand Duke of Lithuania. When this became known, Siemovit responded militarily, laying siege to some Polish towns. Delegates from several towns and cities were ready to name him king in order to prevent an outsider from becoming king, unless Jadwiga returned to Poland as soon as possible.
Once Jadwiga was back in Poland and a coronation of a Polish ruler could take place, things calmed down. She was crowned King of Poland on 16 October 1384. Archbishop Bodzanta, who had supported Siemovit originally, threw his support behind the marriage of Jadwiga and Jogaila. It was Bodzanta who baptized Jogaila, presided over their marriage, and crowned Jogaila. (The illustration shows Jadwiga's royal oath being presented by Bodzanta).
King or Queen—what was her title, really? Consensus is that she was crowned king, and her husband would only take that title if she consented. Some scholars think that was only to distinguish her as an actual reigning queen, rather than just a queen consort who had no authority of her own. But contemporary sources refer to her as "king."
How did the marriage go, and their reign afterward? Let's look at the continuing story tomorrow.