In 1961, Berliners went to sleep and woke up to a city cut in half. East German troops had put up barbed wire overnight, stopping trains, cars and thousands of people from crossing between East and West Berlin

On 13 August 1961, Berliners went to sleep in a city where people could still move between its eastern and western parts. By morning, that reality had changed. During the night, East German troops sealed the border between East and West Berlin and put up barbed wire fences as high as six feet. The sudden move left residents waking up to a city physically divided.

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The border closure also cut train services between the two sides and stopped road traffic from crossing between East and West Berlin.


Thousands were separated overnight

The division was not simply about streets and borders. Families, friends and workers who lived on opposite sides suddenly found themselves cut off from one another.

The new barriers also closed an important escape route for people leaving East Germany. Nearly 12,500 people had fled the country that week, more than 2,000 above the previous week's figure.

In the 24 hours before the border was sealed, around 3,000 people escaped to the West as rumours spread that East German authorities were preparing a major crackdown.

Protesters confronted the new border

Anger quickly spread across West Berlin. Thousands of demonstrators gathered on the western side of the divide, with some attempting to tear down the newly installed barbed wire.

They were pushed back by East German guards carrying bayonets.

West German Chancellor Konrad Adenauer appealed for calm while insisting that Germans living in East Berlin and the Soviet-controlled part of the country remained part of the same nation.

The sudden closure also triggered outrage abroad. Britain said the restrictions violated Berlin's special four-power status, while US Secretary of State Dean Rusk described the move as a serious violation of existing East-West agreements.

Why East Germany sealed the border

The immediate reason was the growing number of people escaping East Germany for the West.

The country had already been struggling to stop the flow. Border guards were intercepting trains and questioning passengers near Berlin, while only a fraction of those travelling were being allowed through.

The exodus became even more intense as people feared that the opportunity to leave would disappear.

That fear proved justified.

By sealing the border, East Germany effectively shut the escape route through Berlin and began a new chapter in the city's history.

The barbed wire erected that night was only the beginning. It was soon replaced by a much more extensive concrete barrier that became known around the world as the Berlin Wall.

For Berliners, however, the impact was immediate. A city they had known as one suddenly had a border running through it, separating people who had gone to bed on one side from those who woke up on the other.