This terminology was used in relation to territories of eastern Germany within the 1937 Germany border, and was based on the terminology used in the Potsdam Agreement. It was used only by the Federal Republic of Germany; but the Polish and Soviet governments objected to the obvious implication that these territories should someday revert to Germany. The Polish government preferred to use the phrase Recovered Territories, asserting a sort of continuity because parts of these territories had centuries previously been ruled by ethnic Poles.