Treaty of Warsaw (1970)

The Treaty of Warsaw (, Polish: Układ PRL-RFN) was a treaty between West Germany and the People's Republic of Poland. 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 Allied powers at the 1945 Potsdam Conference 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. From the Polish perspective, the transfer of these regions was considered to be a compensation for the former Polish territory east of the Curzon Line ("Kresy"), which had been annexed by the Soviet Union in 1939.
In West Germany, Brandt was heavily criticised by the conservative CDU/CSU opposition, who marked his policy as a betrayal of national interests. At the time the treaty was signed, West German commentators sought to maintain that this could not be a final settlement of the Polish border issue, because Article IV of this treaty stated that previous treaties like the Potsdam Agreement were not superseded by this latest agreement; so it might be argued that the provisions of this treaty could be changed by a final peace treaty between Germany and the Allies of World War II—as provided for in the Potsdam Agreement. In actuality, these reservations were for domestic political consumption; as the treaty terms would undoubtedly have been regarded as binding on the Federal Republic and its successors in any tribunal of international law. 
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. In the aftermath of the 1990 Treaty on the Final Settlement with Respect to Germany, the Oder-Neisse line was reaffirmed without any reservation with the German-Polish Border Treaty, signed on 14 November 1990 by re-united Germany and Poland.