Grand Principality of Rus' (1658)

Grand Principality of Rus' (Ukrainian: Велике Князівство Руське, romanized: Velyke Knyazivstvo Rusʹke; Polish: Wielkie Księstwo Ruskie; Lithuanian: Didžioji Rusijos Kunigaikštystė), also known in historiography as Grand Principality of Ruthenia, was the project of the state as a member of the Polish–Lithuanian–Ruthenian Commonwealth in the territory of Kiev Voivodeship, Bracław Voivodeship and Chernihiv Voivodeship. Its creation was proposed by Hetman Ivan Vyhovsky with Yuri Nemyrych and Pavlo Teteria in September 1658 during the negotiations between the Cossack Hetmanate and the Commonwealth.

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