Until the Partitions of Poland, Pławo belonged to Sandomierz Voivodeship. From 1772 to 1918, it was part of the Austrian province of Galicia and remained an insignificant, privately owned village. In early 1937, the government of the Second Polish Republic accepted the project of the Central Industrial Area, which included the construction of a brand new steel mill, together with a settlement for the workers. Before the outbreak of World War II, some departments of the mill were operational and several blocks of flats were built. Construction of the "Southern Works", as the mill was then called, was started in dense pine forests around Pławo in March 1937. Among other things, the plant manufactured artillery cannons.