Union of Mielnik

The Act of Mielnik or Union of Mielnik was an attempt to unite the Kingdom of Poland with the Grand Duchy of Lithuania in 1501. It was not ratified by the Lithuanian Seimas or by the Polish Sejm (see Łaski's Statute). The Act of Mielnik remained just a political project. Despite the failure to unify two countries into a single state, Poland and Lithuania were under a personal union until the Union of Lublin of 1569.

After death of John I Albert, King of Poland, his brother Alexander Jagiellon, Grand Duke of Lithuania, became the most suitable candidate for the new king. Such a move would revive the Polish–Lithuanian union, a personal union between the two states. However, Alexander's ambitions went further. The Act of Mielnik was drafted by Polish and Lithuanian diplomats on 3 October 1501 in Piotrków and confirmed on 23 October 1501 by Alexander (who was already elected as the Polish King but not yet crowned) and few members of the Lithuanian Council of Lords. On 30 October, twenty-seven Lithuanian nobles and boyars agreed to abide by the Union of Melnik. The act declared that Poland and Lithuania would be united into a single state with one ruler, one parliament (Great Sejm), one monetary system, and one army. The separate and independent position of the Grand Duke of Lithuania was eliminated, transferring the title to King of Poland. It meant that Alexander gave up his hereditary rights to the throne of the Grand Duchy. Such declaration sharply contrasted with the Union of Kraków and Vilna of 1499, which envisioned the Polish–Lithuanian union as an alliance of two equal partners.

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