According to the Deulinsky truce, as part of the Seversk land, Nezhin came under the authority of Poland [3] [4] and became part of the Kiev province. In 1625, on the orders of the Polish king Sigismund III, a wood-earthen fortress was erected here [4]. March 26, 1625 Nezhinu granted Magdeburg right [3] [4], land ownership and the coat of arms with the image of St. George. A city government is being created, led by howl. The documents of the 1st quarter of the XVII century. It says about the Nezhin-fortress with 11 towers. Until 1648, the Nezhinskoe Starostvo belonged to the commander of Polish troops, Nikolai Pototsky, and annually paid him up to 300 thousand zlotys.
During the Khmelnitsky uprising in June 1648, the rebels occupied Nizhyn, after which the city became the center of the Nezhinsky regiment [3] [4]. In 1649, the Cossacks of the Nezhinsky Regiment took part in the march on Kodak. Under the terms of the Zborovsky peace treaty of 1649, Nezhin was returned to Poland, but the return of the Polish and Lithuanian gentry caused the uprising of 1650 [4]. Under the terms of the Belotserkovsky peace treaty of 1651, Nezhin was returned to the Polish-Lithuanian Commonwealth [4]. In 1654, by the decision of the Pereyaslavskaya Rada, Nezhin, as part of the Left Bank, became part of Russia [4].
