Nizhyn is a town (population 81,300) on the Oster River and a district center in Chernihiv province. It is the first mentioned as Unenizh under the year 1147 in the Chronicle. The town was destroyed by the Tatars in 1239, and it recovered slowly. In the mid-14th century it came under Lithuanian rule, and in 1514 it was renamed Nizhyn. In 1618 it was taken by Poland. In the Hetman state it was a regiment center (1648-1782) and then a county center of Chernihiv gubernia (1802-1917).