After World War I, in 1918, Poland regained independence, and following the Polish Silesian Uprisings Knurów was reintegrated with Poland. In the interwar period, Knurów developed intensively. New schools, stadiums, a pipeline connecting with Bełk and the first synthetic ammonia plant in Poland were built. In 1923, a monument to the participants of the Silesian Uprisings was unveiled. The coal industry continued growing well in the 20th century, and doubled its output with a new mine being built in 1961 in Szczygłowice.
