Nisko was first mentioned in a document dated 15 April 1439, in which King Władysław III of Varna handed the villages of Nysky, Zaoszicze and Pyelaskowicze to a local nobleman. Furthermore, Nisko was also mentioned by Jan Długosz, in his work "Liber beneficiorum dioecesis Cracoviensis". The establishment of the village was probably the result of catastrophic Mongol Invasion of Poland, which decimated the population of Lesser Poland. Residents of burned villages and towns resettled in the areas north of the enormous Sandomierz Forest. Probably in the second half of the 13th century, a village was established on a hill near the San river. Nisko was a royal village administratively located in the Sandomierz County in the Sandomierz Voivodeship in the Lesser Poland Province of the Polish Crown.