The flag is one of the details that caught the eye of viewers from Bonn who were familiar with the location - and made them sceptical. It’s one of a few hiccups in the otherwise very detailed ARD mini-series.

The red and yellow flag with the city's coat of arms first became the official emblem of the city of Bonn in 1969. The reason was the law on municipal reorganisation. From 1924 to 1969, Bonn's city colours were red and blue - and so was its flag.

The ferry that takes John and Berns across the Rhine also did not exist in 1954. The "Konrad Adenauer" was built in 1967. Back then, in 1954, things were different in terms of traffic in the Federal Republic of Germany. Seat belts didn’t become compulsory in 1974, but the red Borgward Hansa that Toni's fiancé Hartmut (Julius Feldmeier) drives in "Bonn" has three-point belts. The first car to be equipped with them as standard came on the market in Sweden in 1958.

On bicycle paths, too, safety did not play such a big role in the fifties. But if you look closely, you can see the so-called "bicycle safety stripes" in some scenes. But the so-called "Rücksichtsichtungsgebot" (consideration requirement), which legally justified bicycle lanes, did not come into effect until 1975.

In June 2021, filming for the series took place in Bonn, Bad Godesberg and the surrounding area. The film crew also made a stop in Cologne. For example, the former Kaufhof headquarters in Cologne's Cäcilienstraße becomes the Ministry of the Interior, where secret service chief Reinhard Gehlen has his office. The brewery "Sünner im Walfisch" on Cologne's Heumarkt appears in a scene at the end of the first episode but bears the name "Brauhaus zur eisernen Mühle".

People from Bonn do not recognise their city in many scenes. This is because many scenes that are supposed to show the city were shot in Prague. But the production team never intended to deceive anyone: "We dealt with this very openly," ARD programme director Ingrid Günther explained to the GA.

Choosing a different setting for historical series is common today, she says. Structures had changed too much in many cities, including Bonn. "You can no longer shoot historical Bonn on location today," producer Fabian Winkelmann also said at the premiere of the series at the Cologne Film Festival in October 2022, adding that Prague was a better place to film historical Bonn.

"It was never our intention to make places were recognisable," the editorial and production team continues. It is important that "a particular scene is historically plausible". It is also important to reduce costs and keep logistical processes as simple as possible.

With the help of historical documents and on-site research, the film team got an overview in advance. Since the series was not only to be historically accurate, but also to capture the viewer's attention in terms of atmosphere, artistic freedom also played an important role, the team said. The aim is to convey a feeling for the Rhineland during the Bonn Republic.

A real Bonn stamp, authentic posters on the streets and a detailed drawing of the town hall as well as a Rhenish carnival stage - the film team put a lot of work into the details in "Bonn". Actress Mercedes Müller, who plays Toni, even bought herself a typewriter before filming so that she wouldn't look so "helpless" when typing, as she revealed to GA in an interview.

Original text: Franziska Klaes

Translation: Jean Lennox