The ministry was created in 1949 as the Federal Ministry of All-German Affairs (). This ministry was also in charge of matters about the German lands east of the Oder-Neisse-Line which had become a part of Poland. The ministry was renamed in 1969 when Willy Brandt signed a treaty with Poland which said that Poland's western border was along the Oder and Neisse Rivers. This was part of Willy Brandt's ideas of Ostpolitik. At that time Poland was under a communist government. They could not allow West Germany to sign a treaty about East Germany's borders, which is why the treaty says "the western border of Poland" and not "the border between Germany and Poland".