Abstract
This contribution goes back to the genesis of the East-West German border to question the ambivalences of the border fact. The border between the two Germanies was delineated after the Second World War in the context of the Cold War, then was removed with the reunification of the country in 1990. The East-West German border is therefore a thing of the past, yet its legacy continues to affect the contemporary territorial dynamics. The article first specifies the steps in the formation of the delineation and the evolution of the border regime until its disappearance in 1990, to show how the power relations of the Cold War dominated the play of political actors involved in its genesis. It then focuses on the recomposition of the former East- West German border area and describes the mechanisms of selective integration of territories which reveal the permanence and diversity of border effects after its legal disappearance. The third part of the article examines how the disciplinary works consider the ambivalence of the border fact to conceptualize border effects as factors of territorial dynamics.