Mary, Queen of Hungary in the context of "Nicholas I Garai"

Jadwiga (Polish: [jadˈviɡa] ; 1373 or 1374 – 17 July 1399), also known as Hedwig (from German, Hungarian: Hedvig), was the first female monarch of the Kingdom of Poland, as well its last hereditary ruler. She reigned from 16 October 1384 until her death. Born in Buda, she was the youngest daughter of Louis I of Hungary and Poland, and his wife, Elizabeth of Bosnia. Jadwiga was a member of the Capetian House of Anjou, and had forebears among the Polish Piasts.

In 1375, it was planned that when becoming old enough, Jadwiga would marry William of Austria and she lived in Vienna from 1378 to 1380. Louis I is often thought to have regarded her and William as his favoured successors in Hungary after the 1378 death of her eldest sister, Catherine, since the following year the Polish nobility had pledged their homage to Louis' second daughter, Mary, and Mary's fiancé, Sigismund of Luxembourg. However, Louis died, and in 1382, at her mother's insistence, Mary was crowned "King of Hungary". Sigismund of Luxembourg tried to take control of Poland, but the Polish nobility countered that they would be obedient to a daughter of Louis only if she settled in Poland. Queen Elizabeth then chose Jadwiga to reign in Poland but did not send her to Kraków to be crowned. During the interregnum, Siemowit IV, Duke of Masovia, became a candidate for the Polish throne. The nobility of Greater Poland favoured him and proposed that he marry Jadwiga. However, Lesser Poland's nobility opposed him, and they persuaded Elizabeth to send Jadwiga to Poland.

Stephen Tvrtko I (Serbo-Croatian: Stjepan/Stefan Tvrtko / Стјепан/Стефан Твртко; c. 1338 – 10 March 1391) was the first king of Bosnia. A member of the House of Kotromanić, he succeeded his uncle Stephen II as the ban of Bosnia in 1353. As he was a minor at the time, Tvrtko's father, Vladislav, briefly ruled as regent, followed by Tvrtko's mother, Jelena. Early in his personal rule, Tvrtko quarrelled with his country's Roman Catholic clergy but later enjoyed cordial relations with all the religious communities in his realm. After initial difficulties—the loss of large parts of Bosnia to his overlord, King Louis I of Hungary, and being briefly deposed by his magnates—Tvrtko's power grew considerably. He conquered some remnants of the neighbouring Serbian Empire in 1373, after the death of its last ruler and his distant relative, Uroš the Weak. In 1377, he had himself crowned king of Bosnia and Serbia, claiming to be the heir of Serbia's extinct Nemanjić dynasty.

As the Kingdom of Bosnia continued to expand, Tvrtko's attention shifted to the Adriatic coast. He gained control of the entire Primorje region and the major maritime cities of the area, established new settlements and started building a navy, but never succeeded in subjugating the lords of the independent Serbian territories. The death of King Louis and the accession of Queen Mary in 1382 allowed Tvrtko to take advantage of the ensuing succession crisis in Hungary and Croatia. After bitter fighting, from 1385 to 1390, Tvrtko succeeded in conquering large parts of Dalmatia, and Croatia proper. Following the Battle of Kosovo in 1389, his tenuous claim to Serbia became a mere fiction, as the Serbian rulers he sought to subdue became vassals of the victorious Ottoman Empire. The Ottoman Turks also launched their first attacks on Bosnia during Tvrtko's reign, but his army was able to repel them. Tvrtko's sudden death in 1391 prevented him from solidifying the Kotromanić hold on Croatian lands.

Sigismund of Luxembourg (15 February 1368 – 9 December 1437) was Holy Roman Emperor from 1433 until his death in 1437. As the husband of Mary, Queen of Hungary, he was King of Hungary and Croatia (jure uxoris) from 1387. He was elected King of Germany (King of the Romans) in 1410, and was also King of Bohemia from 1419, as well as prince-elector of Brandenburg (1378–1388 and 1411–1415). He was the last male member of the House of Luxembourg.

Sigismund was the son of Charles IV, Holy Roman Emperor and his fourth wife Elizabeth of Pomerania. He married Mary, Queen of Hungary in 1385 and was crowned King of Hungary soon after. He fought to restore and maintain authority to the throne. Mary died in 1395, leaving Sigismund the sole ruler of Hungary.

Elizabeth of Bosnia (Serbo-Croatian: Elizabeta Kotromanić/Јелисавета Котроманић; Hungarian: Kotromanics Erzsébet; Polish: Elżbieta Bośniaczka; c. 1339  – January 1387) was queen consort of Hungary and Croatia, and queen consort of Poland, and, after becoming widowed, the regent of Hungary and Croatia between 1382 and 1385 and in 1386.

Daughter of Ban Stephen II of Bosnia, Elizabeth became Queen of Hungary upon marrying King Louis I the Great in 1353. In 1370, she gave birth to a long-anticipated heir, Catherine, and became Queen of Poland when Louis ascended the Polish throne. The royal couple had two more daughters, Mary and Hedwig, but Catherine died in 1378. Initially a consort with no substantial influence, Elizabeth then started surrounding herself with noblemen loyal to her, led by her favourite, Nicholas I Garai. When Louis died in 1382, Mary succeeded him with Elizabeth as regent. Unable to preserve the personal union of Hungary and Poland, Elizabeth secured the Polish throne for her youngest daughter, Hedwig.