Buchheim was born in Weimar, in the Grand Duchy of Saxe-Weimar-Eisenach, the second son of artist Charlotte Buchheim. She was unmarried, and he was raised by his mother and her parents. They lived in Weimar until 1924, then Rochlitz until 1932, and finally Chemnitz. He began contributing to newspapers in his teens and put on an exhibition of his drawings in 1933, when he was 15. He travelled to the Baltic Sea with his brother, and canoed along the Danube to the Black Sea. After taking his Abitur in 1937, he spent time in Italy, where he wrote his first book, Tage und Nächte steigen aus dem Strom. Eine Donaufahrt, published in 1941. He studied art in Dresden and Munich in 1939, and volunteered for the Kriegsmarine in 1940.
Buchheim was a Sonderführer in a propaganda unit of the Kriegsmarine in the Second World War, writing as a war correspondent about his experiences on minesweepers, destroyers and submarines. He also made drawings and took photographs. As a Leutnant zur See in the autumn of 1941, Buchheim joined KapitänleutnantHeinrich Lehmann-Willenbrock and the crew of on her seventh patrol in the Battle of the Atlantic. His orders were to photograph and describe the U-boat in action. From his experiences, he wrote a short story, "Die Eichenlaubfahrt". Buchheim ended the war as an Oberleutnant zur See.
Post-war career
After the war, Buchheim worked as an artist, art collector, gallery owner, art auctioneer and art publisher. Through the 1950s and 1960s, he established an art publishing house, and he wrote books on Georges Braque, Max Beckmann, Otto Mueller and Pablo Picasso. He collected works by French and German Expressionist artists, from groups including Die Brücke and Der Blaue Reiter, such as Ernst Ludwig Kirchner, Max Pechstein, Emil Nolde, Wassily Kandinsky, Paul Klee, Franz Marc, Gabriele Münter, Alexej von Jawlensky, and Max Beckmann. These works had been derided as "degenerate" during the Nazi period, and he was able to buy them cheaply. In 1973 he published a novel based on his wartime experiences, , a fictionalised autobiographical account narrated by a "Leutnant Werner". It became the best-selling German fiction work on the war. His novel was followed by a non-fiction work, U-Boot-Krieg in 1976, which became the first part of a trilogy, together with U-Boot-Fahrer, and Zu Tode Gesiegt. The trilogy includes over 5,000 photographs taken during World War II. He is also the author of the novels Die Festung, based on travels home across France in 1944, and Der Abschied, about the nuclear-powered cargo vessel NS Otto Hahn. Das Boot was turned into a film in 1981, featuring Jürgen Prochnow as the captain and the debut of Herbert Grönemeyer as "Leutnant Werner". Director Wolfgang Petersen and Buchheim fell out after the author was not allowed to write the script. The film was the most expensive German film ever made. It was nominated for six Oscars. Even though impressed by the technological accuracy of the film's set-design and port construction buildings, Buchheim expressed great disappointment with Petersen's adaptation in a film review published in 1981, describing Petersen's film as converting his clearly anti-war novel into a blend of a "cheap, shallow American action flick" and a "contemporary German propaganda newsreel from World War II". He also criticised the hysterical overacting of the cast, which he called highly unrealistic, despite their talent. Buchheim, after several attempts for an American adaptation had failed, had provided his own script as soon as Petersen was chosen as new director. It would have been a six-hour epic; Petersen turned him down because the producers were aiming for a 90-minute feature for international release. However, today's Director's Cut of Das Boot amounts to over 200 minutes, and the complete TV version of the film is 282 minutes long.
Later life
In later life, Buchheim sought a location to house his art collection, including curiosities ranging from nutcrackers and Thaishadow puppets to mannequins and carousel animals in addition to his important collection of German Expressionist paintings and graphics. A building was constructed in Duisburg, but he considered it unfit, and he turned down offers from Weimar, Munich and Berlin. After years of quarreling with his home town of Feldafing, Bavaria, about his plans for a museum for his art collection, the town's citizens voted against the museum in a referendum. His museum finally opened in 2001 as the Museum der Phantasie in Bernriedon the shore of Lake Starnberg, funded by the government of Bavaria. The entire collection has been estimated to be worth up to $300 million.
Despite a fortune estimated at 14.1 million Swiss francs in the late 1980s, Buchheim became known for :wikt:parsimonious|parsimony. He used a camping table in his dining room, and according to his son, did not pay taxes and reused print blocks made by Otto Müller, forging the artist's initials. He died of heart failure in Starnberg, survived by his wife, Diethild, and two children.
