拉瓦省
Some time in the mid-14th century, Duke Siemowit III, Duke of Masovia held here a meeting of Mazovian dukes and notables. It is not known when Sochaczew received its town charter; by 1368 it had already been a town (civitas). After the death of Duke Siemowit VII, Sochaczew was on February 4, 1476 reintegrated directly with the Kingdom of Poland as a reverted fief. King Casimir IV Jagiellon granted several privileges to the town, including the right to hold annual fairs, on the second Sunday after Easter. Sochaczew was famous for its craftsmen, the town also had a royal mill. In 1478 the building of two churches was completed and in 1487 a hospital was built. At the same time, the town frequently burned in several fires (1461, 1506, 1539, 1590, 1618, and 1644). Sochaczew was a royal town of Poland, administratively located in the Rawa Voivodeship in the Greater Poland Province of the Polish Crown.