Stunned, the people of Berlin watched what was happening in the early morning hours of August 13, 1961: East German security forces sealed off the border between the city's eastern and western sectors. Police, border police and members of combat groups tore up street pavements, erected barricades made of cobblestones, set concrete posts and positioned barbed wire.

Only a few checkpoints were left open, and almost all train and subway lines were disconnected. Berlin was divided and would remain so for 28 years. East Germany, the German Democratic Republic (GDR), had effectively shut in its citizens.

The move was a stroke of luck for the East German Stasi state security, which was run for decades by Erich Mielke in the Ministry for State Security (MfS), according to authors Daniel and Jürgen Ast and Hans-Hermann Hertle. The three expressed their views in a documentary produced by the German broadcaster ARD and Deutsche Welle.

The Wall, and with it the sealing off of East Germany, was the Stasi's "guarantee of power, its lifeblood." From August 13, 1961 to November 9, 1989, tens of thousands of Stasi staff had but one goal, and that was making the Wall insurmountable for East Germans.

'Surveillance more and more important'

Citizens were bugged, their mail opened, and informers targeted friends and even spouses. The film details the mechanisms of the GDR's rule of injustice and the MfS's ever-growing role in the system. "With the Wall, the MfS became more important," says former Stasi lieutenant colonel Harald Jäger in the film. "The assignments became bigger and bigger, in other words: surveillance became more and more far-reaching."

"The situation after August 13 shows that building an anti-fascist protective wall for the citizens of the GDR is good and right. The working class has seized power, never to give it up again," Stasi chief Mielke proclaimed right after the barrier was built.

The bulwark became ever more unsurmountable as the state security's control machinery's overt as well as the more subtle tactics took hold. East Germans who tried to flee the country died in a hail of bullets from border police. "At the time, I felt they were the bad guys," said Jäger. "For us, they were traitors who wanted to betray our state. No matter what their motives, whether they were political or economic — nothing justified an escape," he said.

East Germans suspected of wanting to flee were arrested, ended up in prison or were handed over to West Germany in exchange for foreign currency. Mielke's experts were never far when escape tunnels were discovered, visitors from West Berlin were screened at the border, or recruited as "unofficial collaborators" for the Stasi. The secret police were popularly known as "Horch und Greif "(Listen and Nab).

No plans to build a wall

Walter Ulbricht, head of the East German Socialist Unity Party (SED) ordered the construction of the wall just two months after he had assured the world press that "Nobody intends to build a wall."

Many historians today believe that the SED and Ulbricht wanted to close the border in Berlin much earlier, back in 1952, when the Soviet leadership in Moscow had the inner-German border sealed off. As a result, more and more East Germans turned to the "loophole" West Berlin. The GDR was bleeding out. Ulbricht wanted to plug that hole, so he gave orders to build a wall.

The TV documentary provides a close look at how the GDR regime worked, including explanations by former Stasi officers on rarely shown original historical footage. "On the one hand, the wall had to be maintained mentally and physically; on the other hand, we wanted to present ourselves as cosmopolitan," Günther Enterlein, a former Stasi officer, said. "It was, increasingly, a lot of work."

The regime came under pressure during the last days of the GDR, when Soviet President Mikhail Gorbachev was pushing for glasnost and perestroika, policies of openness and transformation. "Anything that had to do with detente," Enterlein recalls, "was very dangerous for us, the state security."

Between 1961 and 1989, at least 140 people were killed at the Berlin Wall or lost their lives in connection with the GDR border regime. It was the Wall that ensured East Germany's long existence, and the MfS empire, too, owed its heyday to the "anti-fascist protective wall."

With the fall of the Wall, both simply vanished. Ironically, it was a Stasi officer who opened the Bornholmer Strasse border crossing of the Wall on November 9, 1989 — and with it the Berlin Wall.

Deutsche Welle aired "The Stasi and the Wall" on August 11, 2021.

This article has been translated from German.