Replica of the famous sign at the former East–West Berlin border
Emigration restrictions, the Inner German border and Berlin
By the early 1950s, the Soviet method of restricting emigration was emulated by most of the rest of the Eastern Bloc, including East Germany. However, in occupied Germany, until 1952, the lines between East Germany and the western occupied zones remained easily crossed in most places. Subsequently, the inner German border between the two German states was closed and a barbed-wire fence erected.
Even after closing of the inner German border officially in 1952, the city sector border in between East Berlin and West Berlin remained considerably more accessible than the rest of the border because it was administered by all four occupying powers. Accordingly, Berlin became the main route by which East Germans left for the West. Hence the Berlin sector border was essentially a "loophole" through which Eastern Bloc citizens could still escape.
The 3.5 million East Germans who had left by 1961 totaled approximately 20% of the entire East German population. The emigrants tended to be young and well educated. The loss was disproportionately great among professionals — engineers, technicians, physicians, teachers, lawyers and skilled workers.
Berlin Wall constructed
The brain drain of professionals had become so damaging to the political credibility and economic viability of East Germany that the re-securing of the Soviet imperial frontier was imperative. Between 1949 and 1961, over 2½ million East Germans fled to the West. The numbers increased during the three years before the Berlin Wall was erected, with 144,000 in 1959, 199,000 in 1960 and 207,000 in the first seven months of 1961 alone. The East German economy suffered accordingly.
On 13 August 1961, a barbed-wire barrier that would become the Berlin Wall separating East and West Berlin was erected by the East Germans. Two days later, police and army engineers began to construct a more permanent concrete wall. Along with the wall, the 830 mile zonal border became 3.5 miles wide on its East German side in some parts of Germany with a tall steel-mesh fence running along a "death strip" bordered by mines, as well as channels of ploughed earth, to slow escapees and more easily reveal their footprints.
East German guards checking permits of bus passengers going through the checkpoint in October, just after the Wall was built on 13 August 1961
Checks by East German guards
US president John F Kennedy at Checkpoint Charlie in 1963
The Western (foreground) and Eastern (background) checkpoints, with the latter's famous watchtower, which was demolished in 2000