Hadiach, Treaty of [Гадяцький договір; Hadyats’kyj dohovir]. An agreement with Poland signed on 16 September 1658 near Hadiach by Hetman Ivan Vyhovsky after he suppressed a revolt led by the colonel of Poltava, Martyn Pushkar, and severed relations with Muscovy for its violations of the Pereiaslav Treaty of 1654. The Polish commission at the negotiations was led by S. Bieniewski and K. Jewłaszewski; the Ukrainian, by Yurii Nemyrych, the architect of the treaty, and Pavlo Teteria.

According to the treaty, Kyiv voivodeship, Chernihiv voivodeship, and Bratslav voivodeship were to constitute the independent Grand Duchy of Rus’, whose nobles and Cossack starshyna would be equal partners with their Polish and Lithuanian counterparts in a gentry-ruled federation under a commonly elected king. The duchy was to be governed by a hetman elected for life from among four candidates presented by the Ukrainian estates and confirmed by the king. There were to be an autonomous duchy administration, duchy senators and deputies to the common Diet, and a separate court system, treasury, currency, and army of 30,000 registered Cossacks and 10,000 regular mercenaries, paid from public taxes. The hetman and his army were to remain faithful to the Crown and the duchy could not have diplomatic relations or enter into alliances with foreign states. The Polish and Lithuanian armies were denied the right to enter the duchy, except in the event of war, and then they would come under the hetman's command. Up to 100 worthy Cossacks in each regiment could be granted noble status. Poles who had lost their properties during the Cossack-Polish War would have them restored, subject to the hetman's approval. A general anmesty was to be effected. The Orthodox were to enjoy the same unrestricted rights as the Catholics throughout the Commonwealth, and the Orthodox metropolitan of Kyiv and the bishops of Lutsk, Lviv, Peremyshl, Kholm, and Mstsislau were to sit in the common Senate. No Uniate monasteries or churches were to be built in the duchy. Two Orthodox academies (universities)—in Kyiv and elsewhere—were to be opened. An unlimited number of Orthodox schools, colleges, gymnasiums, and printing presses could be established, and the freedom to publish was guaranteed.

In protracted negotiations the Ukrainian envoys strove unsuccessfully to have Volhynia voivodeship, Belz voivodeship, Galicia voivodeship, Podilia voivodeship, Pynsk voivodeship, Starodub voivodeship, and Ovruch voivodeship included in the Grand Duchy of Rus’. The treaty was finally ratified by the Diet on 22 May 1659, but, in spite of support from the Cossack starshyna, Ukrainian nobles, and higher clergy, it did not find favor among the Cossack and peasant masses, which remained hostile to the restoration of de facto Polish rule and the prewar status quo, and to greater stratification among the Cossacks. Because of Ivan Vyhovsky's failures in the war with Muscovy that followed his initial victory at Konotop in June 1659, uprisings against him, and his withdrawal from political affairs and demise, the terms of the treaty were never implemented.

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Herasymchuk, V. ‘Vyhovshchyna i Hadiats’kyi traktat,’ ZNTSh, 89 (1909)
Hadiats’kyi dohovir mizh Ukraïnoiu i Pol’shcheiu 1658 r. (Lviv 1934)
Mishko, S. ‘Hadiats’kyi dohovir,’ Vil’na Ukraïna (Detroit), 23–4 (1959)
Kot, S. Jerzy Niemirycz w 300-lecie Ugody Hadziackiej (Paris 1960)
O'Brien, C. Muscovy and the Ukraine from the Pereiaslav Agreement to the Truce of Andrusovo, 1654–1667 (Berkeley 1963)
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Borys Krupnytsky

[This article originally appeared in the Encyclopedia of Ukraine, vol. 2 (1988).]

Encyclopedia of Ukraine