It was signed by Chancellor Willy Brandt and Prime Minister Józef Cyrankiewicz at the Presidential Palace on 7 December 1970, and it was ratified by the West German Bundestag on 17 May 1972.
In the treaty, both sides committed themselves to nonviolence and accepted the existing border—the Oder-Neisse line, imposed on Germany by the Soviet Union in 1945 following the end of World War II.
This had been a quite sensitive topic since then, as Poland was concerned that a German government might seek to reclaim some of the former eastern territories.
In West Germany, Brandt was heavily criticised by the conservative CDU/CSU opposition, who marked his policy as a betrayal of national interests.
[1] The Treaty of Warsaw was an important element of the Ostpolitik, put forward by Chancellor Brandt and supported by his ruling Social Democratic Party of Germany.