Under the terms of Peace Treaty of Riga the region and the city returned to Second Polish Republic which claimed rights to this territory as a successor to Polish–Lithuanian Commonwealth and as a victorious side of the Polish–Soviet War. By 1939, the Grodno city had 60,000 inhabitants, with Poles and Jews accounting for 60% and 37% of the population, respectively. During Polish rule Grodno was centre of Grodno County in Białystok Voivodeship, but some parts of present Grodno Region was in the voivodeships of Nowogródek and Wilno.