Timothy P. Mulligan
We couldn’t have been sunk by a nicer man.”
- Survivor from the City of Cairo
IN A NAVAL OCFFICER CORPS that prided itself on its modern and middle-class character, and in a combat service often distinguished by mavericks, Karl-Friedrich Merten constitutes a link to the military tradition synonymous with the emergence of modern Germany. A man of medium build, fair skin, piercing blue eyes and a dazzling smile, Merten emerged as one of Karl Dönitz’s top submarine aces during a long and distinguished career in the Reichsmarine and Kriegsmarine. Yet for all of his accomplishments, Merten has received little historical attention. Only the posthumous publication of his memoirs, with invaluable insights into his character and background, has helped redress this imbalance.1 If Adolf Hitler fought World War TI—as characterized by a German aphorism of the time—with a Prussian Army, a National Socialist Luftwaffe,
and the Kaiser’s Navy Merten can be said to exemplify both the first and the last.
To British and American readers the Prussian tradition invokes many images, the worst of
which became familiar as propaganda stereo types in both world wars: excessive
obedience to authority, a veneration of the military and its values, a rigid social structure dominated by an arrogant aristocracy and the subjugation of individual freedoms. But for
German officers it represented a military ethos that blended idealism and stoic courage, unassuming modesty and selfless dedication, personal integrity and a willingness to sacrifice. “To be a soldier, especially an officer,” wrote a young Claus Schenk Graf von Stauffenberg, “means to be a servant of the state, to be part of the state…The military forces and their pillar, the officer corps, represent…the true embodiment of the nation.”
The symbol of this tradition in World War I might have been U-boat ace Lothar von Arnauld de la Perière, descended from a French Huguenot family that had first served in
the army of Frederick the Great and who established still-unsurpassed records for vessels
sunk by a submarine commander (194) while earning praise from adversaries for his daring and chivalry in the treatment of survivors.2
But lineage was not required for membership in the tradition. Karl Friedrich Merten’s family claimed neither lands nor title. Indeed, they could only trace their roots to 17th-century Pomeranian farmers, successive generations of which gradually rose to middle-class prosperity. Merten’s father, also named Carl-Friedrich, studied law at various institutions throughout Germany, then served as a lieutenant in the elite 1. Garde Regiment zu Fuss, the Kaiser’s personal guard. Shortly before his son’s birth on August 15, 1908, in Posen, West Prussia (now Poznan, Poland), the elder Merten had been elected there to the
post of Erster Stadtrat (Town Coundior). Five years later he was appointed Bürgermeister (Mayor) of the city of Elbing, where he would remain—eventually promoted to
Oberbürgermeister (Lord Mayor)3-until his refusal to join the Nazi Party in 1934 led to his resignation.4
Young Karl-Friedrich’s upbringing was strict but fair, and marked by the occasional trouble normal for a high-spirited boy, yet he was to know little of a peaceful, carefree childhood. Before his seventh birthday he experienced the deaths of a sister and brother.
By then his society had already paid the costs of the first year of World War I. Elbing’s contribution to the war effort consisted of its sons and the products of its Schichau shipyards, located on the Elbing River that fed the Frisches Half, a narrow bay to the north. The river’s depth limited the shipyard to such shallow draft warships as fleet torpedo boats, but these vessels sufficed to arouse what would prove to be a lasting nautical interest in Karl-Friedrich. 5
In the war’s last year, at the age of 10, Merten entered a Royal Prussian cadet institute in the Pomeranian town of Köslin. These schools served as a direct pipeline to the military
graduating adolescents with much the same sense of discipline and duty as that received
by West Point and Sandhurst cadets at a later age. His parents considered the move to a
military academy only one of several options, but allowed Karl-Friedrich the ultimate decision. Thus the young Merten himself made the first of several choices that eventually
led to the bridge of a U-boat. The standard introductory speech that welcomed him and his
fellow pre-teenaged comrades to the academy in April 1918 might have been composed with the future U-boat service in mind:
Gentlemen! You have chosen the most beautiful profession there is on this earth. Before
your eyes you have the highest aim there can be. Here we teach you to reach that aim. You
are here to learn that which gives your life its ultimate meaning. You are here in order to learn how to die.
The young Merten thrived in the atmosphere of firm but not overly harsh discipline, which
sharpened and strengthened the rough-hewn character forged in childhood. After two years—with the war ended, the monarchy deposed, and a republic proclaimed—the Royal
Prussian academy became a state Realgymnasium (equivalent to an advanced high school emphasizing modern languages, natural sciences, history and geography), accompanied by
changes in the curriculum and teaching staff. With this symbolic passing of a Prussian institution and tradition, the 12-year-old Merten unknowingly witnessed what would be his own fate.
Yet at the time these changes signified little in Merten’s own life, for while attending the academy he resolved to become a naval officer. In his final year at school he submitted his application, passed his physical examination and visited the naval district office in Kӧnigsberg (now Kaliningrad, Russia), where he was interviewed by then- Korv.Kapt. (Lt.
Commander) Rolf Carls, who would eventually be recommended by Grand Admiral Erich
Raeder as his successor as Commander-in-Chief of the Navy. Before Christmas 1925
Merten learned he had been tentatively accepted as an officer candidate. Immediately after
graduation he reported to Kiel on April 1, 1926, swore an oath of allegiance to the German
Constitution and began the final, grueling battery of physical, mental and character examinations guaranteed to eliminate all but the best qualified.
A few statistics demonstrate the exclusivity of the inter-war naval officer corps. Limited by the terms of the Versailles Treaty to a maxi mum strength of 1,500 officers among 15,000 total personal, the Reichsmarine actually remained below authorized levels. During the 1924-27 period, the navy in fact reduced the number of officers each successive year,
from 1,357 to 1,215. Even as economic prosperity returned to Weimar Germany, service in
the navy attracted large numbers of potential recruits. In 1926, some 44,100 applied to join, of whom a mere 635—a minute 1 .4%—were accepted. Out of the 6,000 officer applicants who reported to Kiel in April, only 104 survived the final weeding-out process:
3 as administrative officers, 21 as engineering officers, and 80 as executive officers ( Seeoffiziere). Among the last was Karl-Friedrich Merten.7
The selection process was not entirely objective. Naval officer candidates usually represented the well-educated and relatively privileged strata of society; characteristics shared with most modern navies. “We were mostly sons of active or reserve officers, and
more than a few were sons of former officers of the Imperial Navy;” observed Merten, whose own father retained reserve officer status in the army. This homogeneity of background and values shaped the character of “Crew 26” (the German Navy designated a
class of midshipmen by year of entry rather than year of graduation) as it would for the German naval officer corps as a whole.8
Merten spent the next four and one-half years in a complex education and training program that contrasted sharply with that of his American counterparts at Annapolis.
Where the latter spent most of their four years in classrooms, German Seekadetten divided their term among various shipboard training assignments and academic instruction.
Merten’s experiences outline this emphasis on seamanship and practical skills:
April-May 1926: “boot camp” basic training at Stralsund
May-October 1926: ordinary seaman aboard sailing ship Niobe
November 1926-March 1928: world cruise aboard light cruiser Emden, including visits to the American West Coast
April 1928-March 1929: classroom instruction at the naval academy Mürwik, located just
outside the Schleswig port of Flensburg
April-July 1929: Torpedo- and Communications School Mürwik
July 1929: Mine Warfare School Kiel
August-September 1929: infantry weapons training, Stralsund
October 1929-February 1930: Naval Artillery School Kiel
February-October 1930: active duty as ensign aboard old battleship Schleswig-Holstein It should be noted that Merten and his comrades received no submarine training, a limitation
imposed by the navy’s lack of operational U-boats. The varied but balanced development
program, however, produced well-rounded executive officers who could learn quickly and
adapt to any naval branch as the need arose. The fruits of the system can be seen in Crew
26’s contribution of 19 U-boat commanders during World War II, five of whom—Merten,
Richard Zapp, Harro Schacht, Wilhelm Rollmann, and Hans-Gerit von Stockhausen—won
the coveted Knight’s Cross ( Ritterkreuz) of the Iron Cross for their achievements. Ten of the 19, however, fell to death or capture before war’s end.9
At the end of his apprenticeship the young Leutnant zur See (ensign) stood an undistinguished 47th in his class, a ranking that did not affect his standard rotation of assignments at sea and on land. Merten’s training emphasized gunnery skills, a
prerequisite for command of surface warships yet to be permitted or built. In particular, his training emphasized large-caliber and anti-aircraft (flak) artillery. He had also
demonstrated a capacity for teaching, which would remain a hallmark of his naval career:
After a year’s duty in interior communications and firing control aboard the light cruiser
Kӧnigsberg, Merten served for two years as an instructor to new midshipmen at the Naval Gunnery School Kiel. There followed two years as a watch and gunnery officer aboard torpedo-boats (in the German Navy approximately equivalent in size to destroyer escorts),
then an extended tour as gunnery officer aboard light cruiser Karlsruhe. By late 1936
Merten—now married and with the rank of Kapitänleutnant (Lieutenant)—was well on his way to a successful if unremarkable career.
Events outside the navy, however, had begun to alter the government and society that Merten served. Adolf Hitler’s nomination to Chancellor in January 1933 marked the end
of the Weimar Republic and the beginning of National Socialism’s epoch in Germany and
Europe. The first ominous signs of change for the armed forces occurred in 1934, as the
oath of loyalty to the German Constitution was replaced by an oath of unconditional obedience to Hitler himself. Like other components of German society the navy—
redesignated the Kriegsmarine in May 1935—would discover too late that it had surrendered control of its destiny.10
Merten’s initial reactions to Hitler, candidly recorded in his memoirs, reveal a political shortsightedness characteristic of the German military at this time. Although his father opposed the Nazis’ intolerance and racial policies, Merten and many of his comrades found their energetic nationalism appealing and ignored larger political issues. The celebration of Hitler’s triumph on January 30, 1933, deeply impressed him: “We were overwhelmed…and evaluated the event for what it was, a national upheaval,” wrote Merten. “Never again in my life would I be so swept up as at that moment.” Hitler’s approval of the murders of his own SA leaders in the summer of 1934 (known as the Röhm Putsch after the SA chief and principal victim, Ernst Röhm) aroused few deep concerns: “From the insular perspective of the Navy order seemed to be restored on the national scene,” explained Merten in his memoirs. “At the time I was convinced of the truth of all official statements…I could not and would not believe that Hitler knew of the
excesses that occurred.” Such expressions reflect the political limitations inherent to the Prussian military tradition, as well as a professional ‘tunnel-vision’ by which some historians characterize the navy. 11
Indeed, Hitler’s rise to power and the general recovery of the German economy brought material benefits and prestige to the navy. Expansion of the service began even before Hitler renounced the arms limitations of the Versailles Treaty, seemingly validated by the
Anglo-German Naval Agreement of June 1935. Kriegsmarine warships participated in
international duties and represented German interests during the Spanish Civil War. The navy’s growth culminated in an ambitious shipbuilding program aimed at restoring
Germany’s position as a world sea power, but construction had barely begun before it was
cut short by war’s outbreak in September 1939. 12
Merten participated in the Spanish actions as second gunnery officer aboard the
Karlsruhe, June-December 1936, and as flak artillery officer aboard light cruiser Leipzig, December 1936-April 1937. In October 1937, he took command of Geleitboot (fast sloop) F-7, beginning “the happiest period of my naval career,” Merten later recalled, for after 11
years of service, he had at last fulfilled the dream of independent command. It would last
only 16 months, however, before external events began to affect assignments. Orders in February 1939 transferred him to another instructional course in large-caliber artillery as the international situation deteriorated.
In June 1939, Merten became training officer for the October (1938) class of officer cadets for a planned cruise to Central America aboard the pre-dreadnought battleship Schleswig-Holstein. In the end the voyage would prove to be much shorter but far more fateful. The aged warship departed in August for a scheduled ceremonial visit to the autonomous Baltic port of Danzig, the disputed status of which served as the pretext for Hitler’s attack on Poland. At 4:47 a.m. on September 1, 1939, Schleswig-Holstein fired the first shots of World War II against the Polish fortified depot at Westerplatte. Merten, directly involved
in the targeting of specific positions, experienced his first action in what would prove to be a week-long operation to reduce the fortifications.
The German navy’s employment of a warship commissioned in 1908 to open hostilities indicates its limited capacity to wage a naval war in 1939. Grand Admiral Erich Raeder had been assured by Hitler of Great Britain’s neutrality in the event of a war over Danzig.
When Raeder learned of the British declaration of war on September 3, the navy commander-in-chief commented that German surface forces were “so inferior in number
and strength to the British Fleet that…they can do no more than to show that they know
how to die gallantly.” Merten felt astonishment at Hitler’s “political dilettantism” in failing to anticipate such developments, but with his “consciousness of duty” he prepared
for the unequal struggle.14
Merten remained aboard Schleswig-Holstein through April 1940, training the next year’s class of officer cadets while participating in minor actions. During this period the small Kriegsmarine achieved its greatest victory in securing the conquest of Norway, but at grievous cost to its surface units (one heavy and two light cruisers and ten destroyers sunk, other warships damaged). Merten’s assignment as a training officer reflected both his instructional skills and advancing age, but he was determined to see combat. He realized
that his best chance lay in the U-boat service. While still performing his training duties he went outside channels to petition the organizational chief of the submarine service and his former superior on the Karlsruhe, Adm. Hans-Georg von Friedeburg, for a transfer.
Although his favorably-disposed comrade carefully avoided any promises, Merten soon received orders to report to torpedo school on May 1, 1940.
The future U-boat ace’s ensuing experiences demonstrate the strength of the Prussian military tradition in its reliance on the character of its officers. Despite his prior specialization in naval artillery and unfamiliarity with submarines, torpedoes, and communications security, five months’ intensive training brought him up to speed in all those subjects. One of his instructors provided the following assessment of Merten at the
conclusion of his training:
A very self-confident and self-reliant officer who is both ambitious and sensitive. He participated enthusiastically in the training course. Through his inclinations and performance he has acquired much knowledge. His calm and assured handling of a
submarine, including submerged maneuvers in the face of contrived difficulties, testifies to his seamanship. His attitude has demonstrated that he is a combat-ready officer who is
suited for command of a combat U-boat. 15
Merten’s training performance so impressed his superiors that they recommended he serve
only a “confirmation” patrol as a commander in-training before receiving his own boat.
This reflected highly individualized evaluations in the selection of submarine
commanders. Although most initially served extended apprenticeships as U-boat watch officers, some received commands directly after training. Thus, Merten and other
Konfirmanden (a German term for youths awaiting religious confirmation, borrowed by the navy) represented an interim category. The virtually identical casualty rates among the three groups suggests that this subjective selection yielded equal results.16
In September 1940, Merten reported to the recently established U-boat base in Lorient, France, where he was assigned to U-38 under Kaptlt. Heinrich Liebe. Merten’s new commanding officer, a member of Crew 27 and a submarine officer since 1935, had just
earned the Knight’s Cross after sinking nearly 90,000 tons of Allied shipping. Even before
Liebe returned from leave, however, Merten availed himself of the opportunity to listen to
evening conversations of such top U-boat aces as Günther Prien, Heinrich Lehmann-Willenbrock, and Reinhard Suhren in the Prefecture, the former French naval barracks.
Merten’s “confirmation” consisted of a winter patrol in the North Atlantic, a two-month ordeal that yielded the meager results of one ship sunk and another damaged. While not
particularly successful from a tonnage-sunk viewpoint, Merten’s maiden voyage furnished
the future ace with what he later described as “a hard yet impressive primer” in the requirements and rhythms of U-boat command. The increasing tempo of the Atlantic battle left little chance to ponder these lessons, for the night that U-38 docked Merten boarded the train bound for Germany and his own submarine.17
Merten’s new command was U-68, a Type IXC boat just being completed in the
Deschimag AG Weser Shipyards of Bremen. Commissioned into service on February 11,
1941, U-68 represented a submarine class designed in the mid-1930’s to perform such strategic missions as reconnaissance, minelaying, and even tactical command tasks. Once
war came, however, the Type IX’s substantial fuel capacity and cruising range of 11,000
miles made her the long-range workhorse of the submarine fleet. Slower to dive and more
sluggish to handle than the smaller Type VIIC, the Type IX quickly proved too vulnerable
to convoy escorts and therefore assumed the role of the “lone wolf,” preying on unescorted shipping for extended periods in areas increasingly removed from the North Atlantic battleground. In this role she proved most effective. Although never amounting to
more than 12% of the U-boat fleet, Type IXC boats alone accounted for approximately 37% of all merchant sinkings.18
It is interesting to note that each of the two mainstays of Dönitz’s U-boat force (Type VIIs and Type IXs) favored different age characteristics in commanders. Type VII boats, operating for relatively short but very combat-intensive periods in battling convoys, demanded the advantages of youth: energy aggressiveness, quick reactions and optimism.
To compensate for command inexperience, Dönitz substituted a tight control of group operations via radio communications. Type IX submarines, which averaged more than 100
days at sea on each patrol, required the virtues of maturity: patience, endurance, insight, coolness under pressure and independent judgment. The selection of Merten for his first U-boat command at age 32 reflected this matching of skills and mission. That only 15 of
203 new submarine commanders in 1941 were older than Merten underscores both his seniority and the predominance of Type VII boats (152 of 203).19
U-68 spent the next four and one-half months in the Baltic on shakedown cruises and training exercises. These sea trials were designed to test the vessel’s seaworthiness and mold boat and crew into a single fighting unit. Through the gamut of engine and diving trials, torpedo firing practices, simulated emergencies and tactical exercises, Merten and his men grew familiar with one another and their vessel. They did not even appreciate that
they had less time in trials and training (138 days) than the standards subsequently maintained (an average of 160 days through 1942-1943), as Dönitz cut corners in 1941 to
build up as large a submarine fleet in as short a time as possible. 20
Merten and his crew very nearly paid the full price for their inexperience on their first patrol, a month-long transfer passage from Kiel to Lorient via the North Atlantic convoy
lanes. Within five days after her departure, U-68 had endured a severe depth-charge attack
and narrowly escaped ramming by a British destroyer south of Iceland. Later, Merten fruitlessly chased an independent steamer, established but lost contact with a British convoy before he had a chance to fire, and claimed the “probable sinking” of a pursuing
corvette though in fact he hit nothing. When internal damage to the main bilge pump left
the boat with only limited diving capabilities, Merten broke off the patrol and headed back to France. Before he could arrive, however, the starboard diesel engine broke down and a
young ensign fell ill with pneumonia. Exhausted and frustrated, Merten tied up to the dock
in Lorient on August 1, his only unsuccessful cruise behind him. 21
Dönitz and his operations chief, then- Kapt. z. S. (Captain) Eberhard Godt, did not blame Merten for his lack of success, for they had selected him for an important albeit controversial mission. In his briefing on September 7, Merten learned he was bound for South African waters, a strategic gamble to surprise Allied shipping there at the expense
of potentially more profitable sinkings closer to home. During the 6,000-mile voyage to the objective, Merten and two other U-boats would be forbidden to attack targets after crossing the equator in order to preserve the element of surprise. In the end things did not work out as planned, but Merten became part of a sea epic.
Departing on September 11, U-68 experienced nothing more exciting than rigorous
practice dives and gunnery drills for the first 10 days of her patrol. During the night of September 21-22, the U-boat joined another southbound submarine, U-107 under Kaptlt.
Günther Hessler, Dönitz’s son-in-law. Together the two boats attacked Convoy SL-87
north of the Cape Verde Islands. Merten and his crew laboriously earned their first success, but its extent is still disputed. According to Merten, U-68 torpedoed and sank three steamers, a claim accepted by U-boat Command and still credited by some
historians. Careful post war analysis has challenged and chipped away at Merten’s claim,
awarding two of the victims to a third U-boat that joined the action, U-103 under Kaptlt.
Werner Winter. Only the 5,300-ton British steamer Silverbelle stands as U-68’s unquestioned initial sinking. Subsequent attacks the next evening on a British destroyer and a tanker proved fruitless, ending Merten’s second convoy action.22
It nearly proved his last. A few days later he proceeded to a secret rendezvous with the homeward-bound U-111, under Kaptlt. Wilhelm Kleinschmidt, at Tarafal Bay in Santo Antao, northernmost of the Cape Verde Islands. The purpose of the rendezvous was to restock Merten’s exhausted torpedo supply. U-67, under Korv.Kapt. Günther Müller-Stöckheim, also arrived to transfer a stricken crewman for passage home. The British Admiralty, alerted to the rendezvous by recently decrypted intercepts of Merten’s request
for the meeting and subsequent replies, dispatched the submarine Clyde to surprise the U-boats. The attempt miscarried, but just barely. U-68 and U-111 had just completed the difficult and dangerous torpedo transfer when Clyde’s torpedoes sped past the stationary U-boats. Unable to sink the Germans with her torpedoes, the British submarine rammed and damaged U-67. Merten did not even realize he was under attack until the torpedo fired
at him detonated harmlessly on the rocks ashore. 23
To this point Merten’s submarine service matched his career: solid but undistinguished.
Good fortune rather than merit seems to have spared him the pitiless fate dealt other inexperienced commanders. His profligate expenditure of torpedoes for rather meager results (17 torpedoes for one undisputed sinking) perhaps testified more to the
unsuitability of Type IXC boats in convoy actions than Merten’s long-range
marksmanship. On the positive side of the ledger, Merten evidenced an ability to extract
the utmost from his crew, as demonstrated by U-68 remaining in action for nearly 50
consecutive hours during the attack on SL-87. A keen analytical mind was also evident in
the detailed recommendations he appended to his war diary, ranging from proposals for radar equipment and signal flares in convoy attacks to suggestions for stronger types of rope lines in U-boat resupply operations.
Merten also mixed his strong, wry sense of humor—a key ingredient in binding captain and crew—with his official duties. Later in the U-boat’s career, floating cases from a victim were eagerly brought aboard only to reveal piles of weather protection coats. The
crew prepared a formal business card for their commander as “Traveller in Oilskins and Wet-Weather Gear.” When advised by his radioman that U-111 had erroneously reported
U-68 as “probably sunk” by the surprise attack in Tarafal Bay, Merten quipped: “That’s how it goes. One morning you wake up a dead man and don’t even know it! ”24 Perhaps U-68’s near escape indeed marked a resurrection, for from that point on her fortunes markedly turned and her captain’s assets came to the fore.
One of these concerned his reputation for snatching and hoarding supplies and spare parts
whenever and wherever possible. “Merten should adopt a hamster or vulture as his boat’s
emblem,” U-67’s chief engineer jested.25 This trait had led Merten to request the torpedo resupply from U-111 in the first place. For the same reason, he asked to rendezvous with
the damaged U-67 to refill his fuel tanks from that homeward-bound submarine. With this
accomplished on October 2, Merten reconnoitered an empty Georgetown harbor on
Ascension Island before proceeding to St. Helena, Napoleon’s final place of exile. The port of Jamestown held only a single ship, the 8,145-ton British oiler Darkdale. Despite the shallow waters, Merten daringly dispatched the large ship literally under the guns of the port’s defenses in the early hours of October 22. The sinking of the Darkdale marked the first U-boat sinking of an Allied ship below the equator. 26
Merten continued southward toward Walvis Bay on South Africa’s Atlantic coast, sinking
two more British merchantmen on the way: Hazelside (5,297 tons) on October 27, and Bradford City (4,953 tons) on November 1. The latter’s sinking demonstrated that Merten, while he had come a long way, still had much to learn. Merten did not detect the Bradford City until U-68 was almost upon her, forcing Merten to dive and maneuver in order to achieve the best angle of attack. After firing his torpedo salvo he veered sharply to port, unaware that his target had done likewise. After hearing the satisfying detonation of a torpedo hit, Merten sought a view of his victim through his periscope. Undoubtedly what
he saw must have been chilling: the looming hull of the Bradford City was only 40 meters distant and still closing with the momentum from her now-dead engines. Merten ordered
all engines reversed but could not avoid a minor underwater collision that punched U-68
to the surface a mere 10 meters from the U-boat’s prey. “Thank God the enemy manned
their lifeboats instead of their guns,” noted a relieved Merten in his war diary: Fortunate to have escaped with only minor damage to the bow, U-68 dove and motored to a safe distance to observe the Bradford City’s final agonies.
Merten continued his cruise off South Africa but did not encounter any other targets, unaware that decrypted intercepts of U-boat messages allowed the British to divert shipping away from U-68 and other boats in the area. The principal enemy for Merten and
his crew remained the draining tropical heat that wrapped the boat in an average (Fahrenheit) temperature of 91°, rising to as high as 140°, in the engine room. 27
On November 11, Merten received word that the Cape Town operation had been broken off, with orders to rendezvous for fuel and provisions with Schiff 16 (Atlantis), the most successful German commerce raider of the war. The refueling on November 13-14, 530
miles SSW of St. Helena, briefly reunited Merten with an old friend and Atlantis’
commander, Korv. Kapt. Bernhard Rogge. After the rendezvous U-68 departed to operate off the Congo. On November 22, as Merten proceeded to a meeting with the supply ship
Python to take on additional torpedoes, he learned that Atlantis, while refueling Kaptlt.
Ernst Bauer’s U-126, had been surprised and sunk by the British cruiser HMS Devonshire.
Determined to cut back his operations and provide assistance in any rescue efforts, Merten
linked up with Python and Korv. Kapt. Hans Eckermann’s U-A on December 1. To his surprise and relief, he encountered Rogge with the survivors of Atlantis. After further discussions with his unfortunate comrade, Merten renewed and almost concluded his fuel
and torpedo resupply when HMS Dorsetshire appeared on the horizon. Merten immediately cast off the fueling lines and crash-dived, but U-68’s newly-acquired weight
of supplies and torpedoes left her out of trim, and he was unable to attain an attack position. When U-A missed the British cruiser with a torpedo spread, Python came under heavy and accurate fire from the British cruiser. Merten surfaced in time to see the Dorsetshire disappearing to the southeast and the German supply ship ablaze and sinking.
With both U-68 and U-A under Rogge’s command, and with that officer aboard Merten’s
submarine, the two boats began a historic rescue mission. The 414 survivors of Atlantis and Python were divided up, each U-boat taking aboard 105 men, the rest placed in 10
lifeboats towed behind the submarines. A handful manned a motor launch used for communications. On December 2, this unusual formation commenced the hazardous
return voyage to France, more than 5,000 miles to the north. U-129 under Korv.Kapt.
Nicolai Clausen joined them the next day, followed by Kaptlt. Joachim “Jochen” Mohr ‘s U-124 two days later Mohr’s perilously low fuel situation was alleviated by Merten’s transfer of some of his own carefully hoarded supply. Four Italian submarines also arrived
between December 14-18 to take on survivors, greatly easing the crowded conditions. U-
68 delivered her survivors to St. Nazaire on Christmas Eve, tying up the next day in Lorient. 28
Thus ended the longest-distance rescue operation undertaken during World War II. All 414
survivors and their rescuers returned home safely, a testament to German seamanship as
well as to the relatively light Allied defenses at the time. Merten had played a crucial role in the rescue as a conclusion to a patrol that had lasted 116 days and covered a distance of 17,600 miles. Ironically, it would not be the last instance where Merten assumed the role
U-68’s next two patrols followed the classic pattern of “lone wolf” operations for Type IXC U-boats in distant waters. After a long journey to its designated area, U-68 stalked unescorted, independently routed merchant ships while evading Allied air and sea patrols.
Each patrol averaged 60 days, and during each Merten and his crew sank seven Allied merchant ships, a total of more than 90,000 tons. From February to April 1942, Merten operated in the region off the west coast of Africa in the area of Freetown and Sierra Leone. In May and June 1942, U-68 prowled new waters in the Caribbean, focusing especially on the Venezuelan and Colombian coasts and the eastern exits of the Panama Canal. On both patrols the U-boat suffered its principal damage not from depth charges or
bombs but from other causes—a further testament to Merten’s leadership in avoiding Allied defenses.
It was during these patrols that Merten’s long-acknowledged skills as a teacher blended with the continued proof of his ability to learn. His marksmanship at the beginning of the
third patrol remained questionable, with only two hits in his first six firings. Thereafter, however, it improved greatly, and Merten was able to record ten hits in fourteen launchings. His record continued to improve through his fourth and fifth patrols when, respectively, 15 of 21 and 14 of 19 torpedoes fired found their marks. Particularly remarkable were four hits achieved at ranges of 2,000 or more meters from submerged firings, and a fifth at a range of 1,000 meters without aid of the temporarily-disabled attack calculator. U-boat Command recommended a standard range of less than 1,000
meters for underwater torpedo attacks, and optimally between 400 and 500.29
Several occurrences made the latter patrol particularly memorable. Shortly after departing
Lorient, defective exhaust valves forced U-68 to divert to El Ferrol, Spain, where a German depot ship repaired the damage with the enthusiastic approval of Spanish Navy authorities. The U-boat’s closest brush with destruction came on June 10 from one of her
victims, the British steamer Surrey, when her cargo of 5,000 tons of dynamite detonated as she plunged into the depths. The force of the underwater explosion caused “the strongest
blow U-68 has yet experienced,” Merten recorded, with damage to the rudder and torpedo
firing controls and almost all breakables on board. Most important for Merten came a signal four days later with news of his decoration with the Ritterkreuz, celebrated by all aboard with an oversized, hand-fashioned Knight’s Cross and a round of beers. The crew
had reason to celebrate: Merten’s patrol marked the most successful U-boat operation (in
tonnage sunk) in the Caribbean throughout the war. 30
For his fifth and final patrol, Merten returned to his objective of a year earlier, Cape Town.
Dönitz’s orders of August 1, 1942, called for U-68 to join four other Type IXC boats and a
“milch cow’ supply U-boat as Gruppe Eisbär (“Polar Bear” Group) to strike Allied shipping in the waters off South Africa. Once again, in order to achieve strategic surprise the boats were prohibited from attacking shipping below a certain latitude. Although the
prohibition was implemented against Dönitz’s better judgment, at least this time U-boat radio communications would not betray them: the addition of a fourth rotor to the
‘Enigma’ encryption device preserved German naval cypher security through most of the
balance of 1942.31
The 6,000-mile voyage to the target area began on August 20. After crossing the equator,
U-68 encountered and sank two independently-routed merchantmen on September 12 and
14. The first sinking yielded the recovery of the captain and chief engineer, both of whom
were handed over to Korv.Kapt. Georg von Wilamowitz-Moellendorf’s supply boat, U-459, during a refueling rendezvous on September 22 southwest of Walvis Bay. Merten proceeded jointly with U-172, under Kaptlt. Carl Emmermann, toward what the Naval High Command hoped would be a surprise attack on Cape Town’s crowded Table Bay.
Instead of heavy traffic, however, the two submarines entered the area on October 6 and
found the brightly-lit roadstead almost empty of shipping. Requests for freedom of action
to pursue more plentiful targets in the Cape Town approaches were denied, a restriction conscientiously observed by Merten but evaded by the more adventurous Emmermann.
Finally receiving permission to attack at discretion beginning October 8, Merten
dispatched six vessels in less than 27 hours. His total might have been even higher had not the steadily-deteriorating weather forced U-68 to break off pursuit of potential victims. By October 14, Merten and his crew were battling hurricane-force winds and rolling seas that
smashed the U-boat’s crockery. When a shift westward led to calmer waters but no targets,
Merten commenced the long voyage home on October 30. 32
En route to France Merten sank his last vessel, the British ship City of Cairo, 500 miles south of St. Helena on the night of November 6. Two single torpedoes sent what Merten
believed to be an 8,000-ton cargo ship to the bottom within two hours. As they monitored
the ship’s distress call and watched the numerous lifeboats go into the water, however, U-
68’s crew realized they had sunk a passenger liner with women and children among its 125 passengers. Because of the recent Laconia incident and consequent non-rescue order by Dӧnitz, Merten could not undertake any serious efforts on behalf of the survivors. He
did, however, go in amongst the lifeboats and assist them by megaphone in recovering other survivors still in the water. After providing the exact course to St. Helena, he departed with the comment, “Goodnight, sorry for sinking you.”
There was little celebration aboard U-68 that night in the belief that the odds against their victims’ survival were too great. In fact, about 200 of the City of Cairo’s 300 original crew and passengers survived. Most followed Merten’s directions and were picked up near St.
Helena 13 days later. One lifeboat became separated and drifted for 51 days before reaching the Brazilian coast, but by that time only two of the original eighteen people on
board were still alive. In 1981 the saga of the City of Cairo and her passengers became the subject of a book and subsequent press stories in England. The public discussion prompted
Merten to write the Sunday Express and provide his own account of the incident. An astonished Merten received over 200 letters from Britain in response, some from the survivors or their families, others from Royal Navy veterans expressing appreciation or interest for his efforts. Three years later the British survivors held a reunion in London and invited their erstwhile foe to attend. One of the survivors later observed: “We couldn’t have been sunk by a nicer man. ”34
On November 17, 1942, Dönitz notified Merten by radio that he had been awarded the Oak Leaves to his Knight’s Cross, only the 147th member of the German Armed Forces to
be so honored. Nineteen days later U-68 tied up at Lorient and Karl-Friedrich Merten stepped off her gangplank for the last time. In only five patrols he and his crew had spent 373 days at sea, traveled nearly 65,000 nautical miles, played a major role in the longest-range rescue operation of the war, and sunk 27 Allied merchant ships totaling 170,248
tons, ranking Merten among the top six U-boat aces of the war.35 Merten also shares in the credit for sinkings accomplished by his former watch officers, whom he tutored in the art
of submarine command: Kaptlt. August Maus, Merten’s first officer from the beginning through December 1942, recipient of the Ritterkreuz for sinking nine ships totaling 59,000
tons and Kaptlt. Alfred Lauzemis, who served successively as second officer, first officer, and commander of U-68 throughout the boat’s history sinking five vessels before U.S.
Navy aircraft sent both to the bottom on April 9, 1944.36
After a two-month stint in command of the 26th U-boat Flotilla in Pillau (now Baltiysk,
Poland), Merten—promoted to Fregattenkapitän (Commander)—settled in as commander
of the 24th U-boat Flotilla in Memel, where from April 1943 to March 1945, he trained
future submarine commanders in what he learned to do so well himself: submerged torpedo firings. Ironically this period coincided with the effective defeat of the U-boat effort in the Atlantic, rendering much of this training academic. Merten’s role in Memel is memorable in quite a different context, as he increasingly found his time taken up in disputes with the Nazi Party Gauleiter for East Prussia, Erich Koch. In late July 1944, when he learned that Koch had ordered 6,000 minimally-trained Hitler Youth teenagers to
man defensive positions outside Memel against the advancing Red Army, Merten took matters into his own hands and ordered the evacuation of the teenagers by sea. Loyalty remained a characteristic of the Prussian tradition; sacrificial fanaticism did not. With Dönitz’s support he withstood the outraged Gauleiter’ s wrath and coordinated that August the general evacuation with his flotilla of 50,000 civilians from Memel—arguably the most significant accomplishment of his German Navy service.
Following the disbanding of his training command on March 12, 1945, Merten served as a
liaison officer to Führer Headquarters in Berlin during the war’s final month. In late April he proceeded with a group of officers to southern Bavaria, the proclaimed but illusory
“Alpine Redoubt” that provided the setting for Merten’s internment after Germany’s capitulation. Unlike so many of his submarine comrades, Merten did not spend an extended period in captivity but was discharged from his 19 years of naval service on June
30, 1945, having attained the rank of Kapitän zur See a mere seven days before the German surrender. By April 1946, he had found work in the French-directed
administration of the Rhine waterways salvaging wrecked barges, and after two years’
employment had apparently settled into his new life.
But the past would not go away. On November 22, 1948, French authorities arrested Merten for his “illegal” sinking of the Vichy French tanker Frimaire in the Caribbean in June 1942. The sinking of this vessel, whose voyage was unregistered with German authorities and which was steaming unlit in a war zone, had prompted an energetic investigation by Dönitz at the time that exonerated Merten. After a six-month trial the French court concurred with this finding and released him. 38
Following retirement from a successful postwar career in shipyard and ship construction
firms, Merten began work on his voluminous memoirs. As some of his contemporaries and a new generation of Germans became more critical of Dönitz and the sacrifices of the
U-boat campaign, Merten increasingly devoted himself to a passionate defense of the attitudes and values that had characterized his own service. 39 In one co-authored book, several published reviews, and personal correspondence he strongly attacked Dönitz’s critics, dismissing their arguments as distortions and hindsight. Yet, when fellow ace and
Knight’s Cross holder Erich Topp publicly criticized Merten’s own writings, Merten responded with a personal appeal to meet privately and discuss their differences, rather than engage in open debate.40 He also found time to complete his memoirs and assist historians in researching the submarine campaign. 41
More than a life passed with Karl-Friedrich Merten’s death due to cancer on May 2, 1993.
A man of personal integrity and courage, Merten never perceived the need to reevaluate the conditions by which such attributes could be abused. Social and political values unreservedly accepted in his youth, blasted and twisted in the cauldron of two world wars,
were discarded by a new generation seeking to redefine the German identity. In all probability the Prussian tradition that guided him, his comrades, and previous generations
died quietly with its last representatives.
The precise meaning of that tradition will continue to occupy and frustrate contemporary
and future historians. Their study will not be made easier by the case of Karl-Friedrich Merten, a dedicated and conscientious officer whose paradoxical legacy combined an extraordinary record of destroyed enemy shipping with a reputation among friend and foe
alike as a savior of lives.