BERLIN — Like many people, Volker Kutscher reads daily newspapers to keep up with things. What’s less usual is that the two papers he relies on, the Vossische Zeitung and the Berliner Tageblatt, have been out of print for more than seven decades.In the papers — which he reads front to back on microfilm in the city’s old state library, weeks’ worth in one sitting — he finds news of violent demonstrations, rising rents, traffic accidents, robberies and murders. He finds reviews of risqué cabarets, modern theater and promising new media (talking films). And in federal politics, there is endless news of weak coalition governments that take far too long to form.To modern Germans all this “news” would seem eerily familiar.The ritual is part of a painstaking research effort that has led to a series of seven best-selling detective novels and “Babylon Berlin,” a blockbuster TV series based on them. The books and the TV show, set in the Berlin of the 1920s and ’30s, have fed into a national discussion about the Weimar Republic, the roots of German democracy, the unfathomable rise of the Nazis and the pressing question of whether history might be repeating itself.Mr. Kutscher has sold more than 1.7 million books in Germany, while tens of millions have watched the TV show there. Two of his books are in print in the United States, with at least two more coming, and Netflix is offering “Babylon Berlin” in America.“His trick is ingenious,” said Tom Tykwer, the principal creator of “Babylon Berlin.” “He’s created a portrait of an era through the lens of genre fiction.”Having spent a good part of his professional life in the two tumultuous decades between two world wars, the 55-year-old former journalist has found success as Germans have increasingly become fascinated with the era.By bringing an American-style detective story to Weimar Berlin — a city Mr. Kutscher calls the most American European city — he has helped popularize an era that has remained shrouded in Germany because of the monstrosities and guilt of the Nazi era that succeeded it. His novels have become almost essential reading in a German discussion about the creation of the modern democratic state, founded 100 years ago.And with the contemporary rise of populist nationalism and the perception that — despite a booming, culturally blossoming era — chaos is at the doorstep, the era is one that many Germans recognize as a mirror — if a warped one — of their present-day country.“I’m very much against direct comparisons: to say that we live in the Weimar Republic again is not — luckily — true,” said Mr. Kutscher, before gamely pointing out the key differences.The modern German economy is humming, whereas in 1929, the year Mr. Kutscher’s first novel is set, the stock market crash had shaken a nation already traumatized by hyperinflation. The current populists, the anti-immigrant Alternative for Germany, who entered Parliament last year for the first time, are not the National Socialists.“But when I started writing, I would not have thought that we would once more live in a time where democracy is similarly endangered,” he said.Daniel Schönpflug, a historian of the era, has praised “Babylon Berlin” for its historical accuracy and for making the era accessible to a wide audience.Mr. Kutscher has done this in part by giving his characters modern habits and placing well-known brands in the story.“Some of my characters shower almost every day, which wasn’t normal then, but I wanted them to be relatable,” he said. “They are just much cleaner than their brethren.”Mr. Kutscher admits that part of his success is luck. His works became best sellers at a time when Germans were ready to re-examine the Weimar Republic. Mr. Tykwer, of “Babylon Berlin,” concurs.“We started writing the script in 2013,” he said, “and it was almost uncanny how the real world around us seemed to want to conform to the era we were describing.”Besides the $45.5 million TV show — the most expensive ever made in Germany — the books have spawned radio theater, a comic book, a podcast and walking tours. Mr. Kutscher created one picture book with Kat Menschik, a well-known illustrator, that tells the back story of one of the characters in his world without being part of the detective series.Like his main character, the dogged and ethically compromised police inspector Gereon Rath, Mr. Kutscher is actually not a Berliner, but a longtime resident of Cologne.He grew up in the 1960s and 1970s in Wipperfürth, a small market town in the west of the country, far from the Berlin hustle. After college, where he studied German literature and history, he landed a trainee position at the Kölnische Rundschau, a regional paper. He was offered a full-time job after graduation, but it came with a catch: He would have to cover his hometown, the very place he was trying to leave.“It was like being the priest or the mayor, maybe less important, but you were visible and had to be responsible,” he said.Mr. Kutscher’s love for Berlin and the Weimar era came through its literature (which because of his novels is experiencing renewed popularity). In the mid-1980s he started regularly visiting the city, going to East Berlin to follow the footsteps of the writers Alfred Döblin and Erich Kästner. He draws on his memories of the grayness he experienced there in imagining Berlin in the 1920s, he said.“The city was much less colorful then,” he said during an extensive interview in a hip hotel in Berlin, right at a spot where a fictional tobacconist introduced Inspector Rath to Camel Cigarettes in 1931.After seven years as the local editor of the paper, he quit to focus on his project: a series of books that would document the Weimar Republic and the first years of the Nazi era. Since he had written only three relatively unknown local crime thrillers (a new genre in Germany at the time), finding a publisher to consider such a hefty project took nearly two years. By the time Kiepenheuer & Witsch signed on for the first book — with options for the following manuscripts — he had almost given up and was looking for his next job in journalism.“The goal really was just to be able to do this full-time,” he said. That was assured after his third book, “Goldstein,” came out in 2010 and made it onto the German best-seller list (it’s available as an e-book in the United States from Picador Press, with a paperback to follow next year).His latest novel, “Marlow,” yet to be translated, is set in the city after the Nazis have come to power. The Vossische Zeitung has closed after a nearly two-century run, while the liberal Berliner Tageblatt, in Jewish hands since its founding in 1872, has been taken over by the Nazis.Mr. Kutscher still forces himself to read it, to know what his characters, navigating Berlin in 1935, would have read.“It’s just awful now,” he said.