First recorded mentioning of Żabno dates back to the 12th century, when Prince Bolesław V the Chaste granted the settlement to a knight known as Świętosław. It became a center of communication and trade, due to a convenient location along a merchant route from Wojnicz and Pilzno, to Opatowiec and Nowy Korczyn. It is not known when Żabno received its town charter. This must have happened before the year 1385, as on January 26 of that year, Queen Jadwiga of Poland, upon request of Spytek of Melsztyn, confirmed Żabno's Magdeburg rights. Little is known about town's early history, as few documents have been preserved. One of the few established facts is that in 1394, King Władysław Jagiełło visited the town with his court, on the way to Nowy Korczyn.