In case you didn't know and are interested: There is a quite recent publication on the actual journey upon which "Das Boot" was based:
Gerrit Reichert:
U 96 - Realität und Mythos: Der Alte und Lothar-Günther Buchheim
It is largely based upon the diary that the late Friedrich Grade
https://de.m.wikipedia.org/wiki/Friedrich_Grade, U96's chief engineer kept (against orders). It sheds a totally different light on the relationship between Buchheim (Lt Werner) on the one hand and the sub's crew, especially the old man, on the other.
This book somewhat exemplifies el Quijote's and muck's statements: Buchheim like others (Werner, Carrell, Konsalik, maybe Brennecke, too) tried, and managed to white-wash their own doings in the Third Reich (most of them playing a more or less big role in the propaganda apparatus) and at the same time self-aggrandize their own actions.
Newer publications, amongst others, tend to put these authors back into their historical role. (In my opinion, we still carry a lot of propaganda inventions of WWII and its aftermath in our minds without knowing it - amongst others the total lack of political ambitions and thought and involvement of the Wehrmacht - and of course the superior quality of its officers and men as compared with their adversaries.)
U96 (the book) was widely acclaimed in its time and as far as I have seen, was on display in bookshops that usually seldom to never exhibited naval or military literature. "Das Boot", at the latest since it was shown on TV and at cinemas has had a deep impact of the little knowledge Germans have on the war at sea. So this book in consequence also reached a relatively wide audience.
If you'd like to read another more down to earth and less heroic novel about the Kriegsmarine's small fry's war at sea, look out for Wolfgang Ott: "Haie und kleine Fische". But don't be surprised: it also deals with young mens' thoughts and activities when on liberty ashore - quite similar to Buchheim. There's a movie from the 60s as well as a book. It's more than 25 years since I watched /read both but found them both quite worth the while. The book sometimes is a bit more gut-heabing than "Das Boot".
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