From Poland: The First Thousand Years, by Patrice M. Dabrowski (Cornell University Press, 2014), Kindle pp. 116-120:
Kazimierz IV Jagiellon married Elizabeth, the daughter of Albrecht Habsburg and granddaughter of Sigismund of Luxemburg. She produced for him an abundance of heirs: six sons and five daughters. This situation was enviable in a world where dynasties so often died out but also challenging, in that all this royal blood cried out for distinguished posts. And indeed: the royal pair strove to find places for their children to rule, capitalizing on the still prevalent medieval idea that royal bloodlines were important. All their children were brought up for exalted positions, and many of them would rule on one throne or another (sometimes on several at once). They were given an excellent education under none other than Jan Długosz, former secretary to Bishop Zbigniew Oleśnicki and Kraków canon. His greatest and certainly most durable claim to fame came from his twelve-book Latin-language history of Poland, Annales seu Cronicae Regni Poloniae (Annals or Chronicles of the Kingdom of Poland), which covered the history of the country up to 1480. In addition to royal heads of state, the pupils of the royal tutor Długosz included a future cardinal (Kazimierz’s son Fryderyk) as well as a future saint (his namesake, Kazimierz).
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A longer period ensued before the same Jagiellon gained control over the Hungarian throne. In Hungary, it was the Transylvanian-born Matthias Corvinus (son of János Hunyadi) who was chosen king in 1458, doubtless in part due to the memory of his father’s military prowess, which he seemed to have inherited. Better known by a nickname taken from the raven (Latin: corvus) on his escutcheon, Corvinus was the first commoner to ascend to the Hungarian throne, and he was an outstanding ruler. He made inroads into what had been Poděbrady’s holdings, annexing Moravia and Silesia as well as the Lusatias. At one point the Hungarian king even occupied Vienna, the Habsburgs’ capital, which he retained control of until his death in the spring of 1490. Władysław followed these developments closely. To strengthen his position as a candidate for the throne, that autumn the Jagiellon secretly married Corvinus’s widow, and she sought to have him gain power in Hungary. Although it may seem paradoxical, there was opposition from Władysław’s own father, who wanted to seat another son, Jan Olbracht, on the Hungarian throne. The men even fought two wars over the succession (so much for family unity). Yet, once the Habsburgs got involved, the tide turned against Jan Olbracht. To keep Hungary and Bohemia safely in Jagiellonian hands, Kazimierz IV Jagiellończyk threw his weight behind his eldest son, already seated on the Bohemian throne.
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Although in Hungary he was officially hailed as King Ulászló II, Władysław came to be known there as King Bene—this, apparently, from always answering “very well” (bene) to whatever was asked of him. Among other things, in 1514 he allowed the Hungarian nobles to establish the so-called Tripartitum, a new codification of Hungarian law that gave them increased power over their peasants. Yet the Jagiellon was indeed the true ruler of the two countries, though he reconfigured them somewhat, restoring Moravia, Silesia, and Lusatia to the kingdom of Bohemia (they had come under Hungarian control under Matthias Corvinus). He also notably restored Vienna and eastern Austria, which had been occupied by Corvinus, to the Habsburgs—a move that, while keeping Habsburgs from conniving to unseat him, would nonetheless strengthen a future rival to Jagiellonian rule. Władysław lived until 1516, to be succeeded on both thrones by his son Louis (Czech: Ludvik; Hungarian: Lajos). In this way, Jagiellons came to control both the Bohemian Crown of Saint Wenceslas and the Hungarian Crown of Saint Stephen.
But this was only the near realm of Central Europe. All five daughters of Kazimierz Jagiellończyk fared well in the marriage game also. They demonstrated the potential impact of the Jagiellonian dynasty on the German-speaking world. Jadwiga married George the Rich, prince of Bavaria. Another daughter, Barbara, wed another George the Bearded, duke of Saxony. Two other sisters, Anna and Elżbieta, married the dukes of Pomerania and Legnica (German: Liegnitz), respectively; each of these husbands (Bogislaw X and Friedrich II) would be given the sobriquet of Great. Their other sister, Zofia, was the wife of Friedrich von Hohenzollern-Ansbach, elector of Brandenburg. Zofia would give birth to Albrecht von Hohenzollern-Ansbach, who (as we shall see) would be last in the long line of grand masters of the Teutonic Order on the Baltic Sea coast.
All this left the Jagiellons seemingly in a strong position. Men from the dynasty came to control all of East-Central Europe: from Hungary and Bohemia through Poland and Lithuania, putting them in a position to rule over vast territories and peoples. Kazimierz IV Jagiellon ruled Poland and Lithuania, while his son Władysław had ascended to the Crowns of Saint Wenceslas and Saint Stephen—that is, Bohemia and Hungary, respectively. Jagiellons would rule uninterruptedly over these four political entities for some thirty-six years: from 1490 to 1526, their power extended from the Baltic to the Adriatic and nearly all the way to the Black Sea.
That the Jagiellonian Moment in Central and Eastern Europe is so little known has to do with both the nature of Jagiellonian rule and the times in which they lived. With the exception of Lithuania, the countries they ruled—Poland, Bohemia, Hungary—were elective monarchies with relatively powerful, noble-dominated parliaments. In these countries, what was wanted was not an absolute monarch but, rather, someone who would work with the existing parliamentary bodies.
Far Outliers 