Toruń, Poland
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| July 26, 1501 in Wawel Cathedral
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| September 23, 1492 in Wawel Cathedral, Kraków
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| Jagiellon dynasty
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| Pogoń Litewska.
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| Casimir IV of Poland Elisabeth of Austria
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Jan I Olbracht (1459 – 1501) was King of Poland (1492 – 1501), Duke of Głogów (1491 - 1498).
As crown prince, he distinguished himself by his brilliant victory over the Tatars at Kopersztyn (1487).
In 1490, the Hungarian nobility proclaimed Jan Obracht King of Hungary at the Rokos diet. He was, however, defeated by his brother, Bohemian King Ladislaus II. In 1492 Jan Olbracht succeeded his father as King of Poland.
Losses of revenue consequent to the secession of Lithuania placed Jan Olbracht at the mercy of the Polish sejmiks, or local diets, where the szlachta made their subsidies dependent on the king's subservience.
Primarily a warrior with a strong taste for heroic adventure, Jan Olbracht desired to pose as the champion of Christendom against the Turks. Circumstances seemed, moreover, to favor him. In his brother Wladislaus, who as king of Hungary and Bohemia possessed a dominant influence in Central Europe, he found a counterpoise to the machinations of Emperor Maximilian, who in 1492 had concluded an alliance against him with Ivan III of Muscovy, while, as suzerain of Moldavia, Jan Olbracht was favorably situated for attacking the Turks. At the conference of Leutschau (1494), the details of the expedition were arranged between the kings of Poland and Hungary and Elector Frederick of Brandenburg, with the co-operation of [[Stephen III of Moldavia|Stephen], hospodar of Moldavia, who had appealed to Jan Olbracht for assistance.
In the course of 1496 Jan Olbracht with great difficulty collected an army of 80,000 men in Poland, but the crusade was deflected from its proper course by the sudden invasion of Galicia by the hospodar, who apparently — for the whole subject is still very obscure — had been misled by reports from Hungary that Jan Olbracht was bent upon placing his younger brother Sigismund on the throne of Moldavia. Be that as it may, the Poles entered Moldavia not as friends but as foes, and after the abortive siege of Suczawa, were compelled to retreat, see Battle of the Cosmin Forest for more.
The insubordination of the szlachta seems to have been one cause of this disgraceful collapse, for Jan Olbracht after his return confiscated hundreds of their estates; in spite of which, to the end of his life he retained his extraordinary popularity. When the new Grand Master of the Teutonic Order, Frederic of Saxony, refused to render homage to the Polish crown, Jan Olbracht compelled him to do so. His intention to still further humiliate the Teutonic Order was frustrated by his sudden death in 1501.
A valiant soldier and a man of much enlightenment, Jan Olbracht was a poor politician, recklessly sacrificing the future to the present.
