The book, based on little-known sources, explores the main international treaties of Bogdan Khmelnitsky - with Islam Giray III in March 1648, the Zborovsky Treaty of 1649, with the Sultan of the Ottoman Empire Mehmed IV in 1650-1651, Chigirinsko-Moskovsky (the so-called Pereyaslavsky) agreement of 1654. The content of the formula "under the high hand" is widely covered as a manifestation of the Ukrainian mentality of the middle of the 17th century. For the first time in historiography, the ceremonial and legal aspects of the agreement of 1654 are clearly distinguished. The last treaty during the life of the Great Hetman is the Swedish-Cossack, which was signed by Ivan Vygovsky. New views are being substantiated on the ties of the state of Bogdan Khmelnitsky with the Crimean Khanate, the Ottoman Empire, Poland, the Moscow kingdom, and Sweden.