The Duchy of Sandomierz was created in 1138 by King Bolesław III Wrymouth, who in his testament divided Poland into five principalities.

It included such cities and towns of contemporary Poland, as Dębica, Dęblin, Iłża, Kielce, Kolbuszowa, Końskie, Kozienice, Lipsko, Mielec, Nisko, Opoczno, Ostrowiec Świętokrzyski, Pińczów, Pionki, Radom, Ropczyce, Ryki, Stalowa Wola, Starachowice, Staszów, Szydłowiec, Tarnów, Tarnobrzeg and Włoszczowa.

The shape of the voivodeship remained unchanged from 1474 to the first partition of Poland (1772), when the Habsburg monarchy annexed the area south of the Vistula, with Dębica, Kolbuszowa, Mielec, Nisko and Tarnów.

1471, the Land of Lublin was separated from it (...) The area of Sandomierz Voivodeship was 467 square miles, with 374 Roman Catholic parishes, 100 towns, and 2,586 villages.

In the early 16th century the voivodeship had 9 counties: Sandomierz, Wislica, Checiny, Opoczno, Radom, Szydłów, Stezyca, Pilzno and Tarnów.

The voivodeship had several starostas, who resided in such towns, as Sandomierz, Radom, Checiny, Opoczno, Nowy Korczyn, Stezyca, Wislica, Pilzno, Stopnica, Solec nad Wisla, Zawichost, Szydlow, Przedborz, Ropczyce, Ryczywol, Radoszyce, Ryki, Zwolen, Gołąb and others.