Question: Where was the "U-96" based in real life in late 1941?
About the article "Das Boot", section "Historical accuracy".

Candidate passages:
In the film, there is only one ardent Nazi in the crew of 40, namely the First Watch Officer (referred to comically in one scene as "Unser Hitlerjugendführer", "Our Hitler Youth Leader"), with the rest of the officers either indifferent or, in the Captain's case, openly cynical.
The enlisted sailors and non-commissioned officers are portrayed as apolitical.
In his book "Iron Coffins", former U-boat commander Herbert A. Werner states that the selection of naval personnel based on their loyalty to the party occurred only later in the war (from 1943 onward), when the U-boats were suffering high casualties.
At that stage in the war, morale was surely declining and this degree of skepticism may have occurred.
In support of "Das Boot" on this subject, U-Boat historian Michael Gannon maintains that the U-boat navy was one of the least pro-Nazi branches of the German armed forces.
Even though the beginning and the end of the film occur in the port of La Rochelle, it does not correspond historically.
The submarine base in La Rochelle was not functional before November 1941, and at the time of the film the port was dried up.
Moreover, none of the British fighter-bombers of late 1941 to early 1942 had the range to bomb La Rochelle from bases in the U.K.; however, it is possible the fighters were carrier-based and not land based.
While Saint-Nazaire was the base used in the novel, the film was changed to La Rochelle because its appearance had not changed to such a large degree in the years since World War II.
In real life, the "U-96" was based at Saint-Nazaire in late 1941.
It survived this period, but much like its on-screen fate, it actually was sunk by Allied bombers at its berth in Wilhelmshaven in March 1945.
On 1 May 1941 "U-37" was reassigned to the 26th U-boat Flotilla, based at Pillau, as a training U-boat.
She was transferred to the 22nd U-boat Flotilla, based at Gotenhafen on 1 April 1942, and finally to the 4th U-boat Flotilla on 1 July 1944, where she remained until the end of the war.
She was scuttled by her crew in May 1945. 
For her second foray, "U-96" departed Lorient on 9 January 1941 and returned to the waters west of Scotland, sinking the on 16 January and the a day later.
The "Almeda Star" was lost with all hands and passengers, a total of 360 people.
"U-96" docked once more in Lorient on the 22nd. 
Lehmann-Willenbrock was born on 11 December 1911 in Bremen, German Empire.
He joined the "Reichsmarine" of the Weimar Republic in April 1931 as a member "Crew 1931" (the incoming class of 1931), with the rank of "Seekadett", serving on a light cruiser and a sailing school ship before he transferred to the "U-Boatwaffe" in April 1939, five months before World War II began.
Upon serving as an executive officer on , he was promoted to "Kapitänleutnant" and took command of in December 1939.
Both "U-8" and "U-5" were Type II submarines.
His first patrol, which lasted 15 days, was along the coast of Norway during Operation Hartmut, the U-boat operation in support of the invasion of Norway.
No ships were sunk.
Upon the return of "U-5", Lehmann-Willenbrock was transferred to the newly commissioned , a Type VIIC U-boat whose crew underwent three months of training before being put onto active duty.
During three patrols under Willenbrock's command, "U-96" sank 125,580 tons of enemy shipping.
The third patrol alone resulted in seven ships sunk, for 49,490 tons.
In 1941 Willenbrock's sinkings with "U-96" included three British troop ships: (16 January), (17 January) and (15 July); each with considerable loss of life.
The seventh patrol was the approximate time that Lothar-Günther Buchheim boarded "U-96" and documented the boat's successes in his book "Das Boot".
Willenbrock earned all of his medals during his patrols with "U-96".
Lehmann-Willenbrock left "U-96" in March 1942 to be promoted to "Korvettenkapitän" and appointed "Flottillenchef" of the "9th U-boat Flotilla", stationed in Brest.
On September 2, 1944 he assumed command of and escaped the besieged Brest just a few days before the town's surrender.
He reached Bergen, Norway on October 23.
In Bergen he was appointed "Flottillenchef" of the "11th U-boat Flotilla" in December, and held the position until the German surrender in Norway on 9 May 1945.
After a year in captivity, Lehmann-Willenbrock returned to Germany in May 1946, salvaging ships in the River Rhine.
In 1948, he left Germany aboard his ship, "Magellan", with three of his friends to Buenos Aires.
After returning to Germany, he served as captain on several merchantmen, and was appointed captain of the German freighter "Otto Hahn", the first of only four merchant cargo nuclear ships.
Buchheim's book "Der Abschied" ("The Goodbye") describes one of its voyages, which Buchheim joined as a passenger.
He was decorated in 1974 with the "Bundesverdienstkreuz am Bande" (Federal Merit Cross on Ribbon).
In 1982, Lehmann-Willenbrock accompanied Wolfgang Petersen and the "Das Boot" cast and crew as an advisor to the film.
Afterwards, he returned to his home at Bremen, where he remained until his death. 
"U-558" was laid down on 6 January 1940 at Blohm + Voss in Hamburg, Germany as 'werk' 534 and launched on 23 December 1940.
She was commissioned on 20 February 1941, with "Oberleutnant zur See" Günther Krech in command.
Her service began with the 1st U-boat Flotilla where she conducted training before moving on to operations, also with the 1st flotilla, on 1 May 1941.