LTReikšminiai žodžiai: 1709 m. Poltavos mūšis; Abiejų Tautų Respublika (ATR; Rzeczpospolita Obojga Narodów; Žečpospolita; Sandrauga; Polish-Lithuanian Commonwealth); Abiejų Tautų Respublika (ATR; Rzeczpospolita Obojga Narodów; Žečpospolita; Sandrauga; Polish-Lithuanian Commonwealth); Didžioji Rusios kunigaikštystė; Hadiačo unijos idėja; Lenkija (Lenkijos karalystė. Kingdom of Poland. Poland); Lietuvos Didžioji Kunigaikštystė (LDK; Grand Duchy of Lithuania; GDL); Mazepa; Ukraina (Ukraine); Unija; Battle of Poltava; Grand Duchy of Ruthenia; Mazepa; The Grand Duchy of Lithuania; Union of Hadiach idea.
ENUp to this very day, the Union (agreement) of Hadziacz, signed on 16 September 1658 between the Commonwealth of the Two Nations and Ukraine, gives rise to lively discussions among historians. One of the reasons is the fact that the Union had never been implemented. Its idea was revived fifty years later, when during the first years of the Northern War Jan (Ivan) Mazepa, the Hetman of Ukraine, embarked upon an attempt at conducting a political turnabout and based himself upon an alliance with the Commonwealth and Sweden against Russia. First Polish-Ukrainian contacts took place in the autumn of 1705. An essential role was played by Anna Dolska, who was to have informed the Hetman about assurances of assistance from Stanisław Leszczyński. The secrecy surrounding the negotiations with Poland and Sweden was the reason why we do not have any convention documents at our disposal. All data are taken from indirect sources demonstrating that Mazepa, together with his loyal Cossack elders, returned to the idea of the Union of Hadziacz. Decisions made in Hadziacz were perceived as a protection of privileges and liberties, and a guarantee of the autonomy of Ukraine. Plans for freeing Ukraine from Russian rule ultimately vanished after the defeat suffered by Charles II at the battle of Połtawa on 8 July 1709. [From the publication]