The Upper Silesia 1980 strikes were widespread strikes, which took place mostly in the Upper Silesian mining city of Jastrzębie-Zdrój and its surroundings, during late August and early September 1980. They forced the Government of People's Republic of Poland to sign the last of three agreements establishing the Solidarity trade union. Earlier, agreements had been signed in Gdańsk and Szczecin. The Jastrzębie Agreement, signed on September 3, 1980, ended Saturday and Sunday work for miners, a concession that Government leaders later said cut deeply into Poland's export earnings.