Busk was granted town charter in 1411 by Siemowit IV, Duke of Masovia. In the Polish–Lithuanian Commonwealth, it belonged to the Belz Voivodeship, and was the seat of a separate administrative unit, the Land of Busk. The town remained part of Poland until the first partition of Poland (1772), when it was seized by the Habsburg Empire, and remained in Austrian Galicia until late 1918. In the interwar period, Busk belonged to Kamionka Buska County, Tarnopol Voivodeship, until Soviet invasion of Poland (September 1939). In 1913, the population of Busk was 8,000, including 3,500 Poles, 2,700 Jews and 1,800 Ukrainians.