Cryptologia, 31:152–163, 2007
Copyright Taylor & Francis Group, LLC
ISSN: 0161-1194 print
DOI: 10.1080/01611190601038225
Wilhelm Fenner and the Development of the
German Cipher Bureau, 1922–1939
DAVID ALVAREZ
Abstract Wilhelm Fenner was the central figure in the evolution of the German
Cipher Bureau between 1922 and 1939, and a major personality in the history of
German communications intelligence in the interwar period. Under his direction,
the Cipher Bureau evolved into a highly professional communications intelligence
service, which scored impressive cryptanalytic successes against the diplomatic
and military systems of many countries.
Keywords Cipher Bureau, Germany, OKW=Chi, Wilhelm Fenner
Introduction
The declassification in recent years of almost all of the records of American and
British communications intelligence operations up to the end of the Second World
War has provided an opportunity for historians to explore what had long been some
of the most inaccessible terrain in the landscape of twentieth century diplomatic and
military history. Not only have the new sources provided details concerning the cryptanalytic capabilities and operations of various governments, but they have also
introduced historians to a cast of characters who played leading roles in the hitherto
secret dramas (and comedies) of the intelligence world. Among historians of cryptology, some of these personalities (William Friedman, John Tiltman, and Alan
Turing) have acquired the status of celebrities.
Not surprisingly, the documentation now available at College Park and Kew has
a decidedly Anglo-American bias. For all their revelations concerning the organization and operation of American and British communications intelligence agencies in
the period 1914–1945, the recently released files tell us less about the agencies of
other major powers (France, Germany, Italy, Japan, and the Soviet Union) and next
to nothing about the activities of secondary powers (Czechoslovakia, Netherlands,
and Spain) that are known to have possessed cryptologic capabilities in this period.
Similarly, French, German, Italian, and other ‘‘foreign’’ cryptologists have not had
the chance to stand in the historical spotlight that has illuminated the accomplishments
of their American and British counterparts. As a small step toward redressing this
imbalance, this article will consider the career of Wilhelm Fenner, the long-serving
chief of cryptanalysis in the Cipher Bureau of the post World War I German Defense
Ministry and its Nazi-era successor, OKW=Chi (Oberkommando der Wehrmacht=
Chiffrierabteilung, and a central figure in the cryptologic history of Germany.
Address correspondence to Dr. David Alvarez, Department of Politics, Saint Mary’s College of California, Moraga, CA 94575, USA. E-mail: dalvarez@stmarys-ca.edu
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Wilhelm Fenner
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Figure 1. Wilhelm Fenner.
Early Career
Wilhelm Fenner was born on 14 April 1891, in St. Petersburg. His father was the
managing editor of the St. Petersburg Zeitung, the Russian capital’s German language daily. The sixth of seven children, the young Wilhelm received his early education at home before enrolling at the age of eight in St. Anne’s—an Evangelical
Lutheran school. After primary school, he attended the school’s gymnasium (university preparatory school) from which he graduated with distinction in 1909. After a
brief spell as a tutor in the family of a German nobleman, in the autumn of 1910,
he matriculated in the Royal Institute of Technology in Berlin, where he studied
engineering, chemistry, and metallurgy. In the summer of 1914, as newspapers
around the world headlined the assassination of the heir to the Austro-Hungarian
throne, Archduke Ferdinand, and his wife, and Europe began the slide toward
war, Fenner passed the preliminary exams for his degree [8. p. 1].1
With the outbreak of war in August 1914, Fenner’s family could no longer contribute funds for his education, so he had to abandon the classroom for the workplace. He took a position as an engineer at Siemens, one of Germany’s largest
industrial concerns, where he was assigned to a project developing electrical systems
1
After World War II Wilhelm Fenner composed for American intelligence several reports
on German communications intelligence. These papers covered various topics from the period
1922–45. Unless otherwise specified, information concerning Fenner’s life and career are
drawn from the autobiographical paper listed as item 8 in the references.
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for warships. He fully expected to be called up for military service in a railway
regiment, but to his surprise he was drafted in December 1914 into the 5th Grenadier
Regiment, which, after absorbing significant losses on the Russian front, needed
replacements. His service with the grenadiers was brief—for within a month, he
received orders to report to a unit of mountain troops then headquartered in
Munich. He saw service in Russia, France, and Serbia and eventually joined the staff
of the Tenth Army. In his postwar testimony he glossed over this wartime service,
noting only that he was commissioned a lieutenant in 1917; but, another source suggests that he worked as a military intelligence officer [12, p. 191]. After the armistice
in November 1918, he remained under arms as a member of one of the Free Corps
battalions of demobilized soldiers and freebooters who offered their services to
political groups jockeying for position and power in the political and economic
uncertainty of Germany in the first months of peace.
Claims that after the First World War Fenner served Germany as an intelligence
operative in the Middle East where he was arrested and imprisoned for a year by the
British are unconvincing [12, p. 191]. During his extensive debriefings by American
interrogators after the Second World War, Fenner made no mention of such service.
Since he freely provided details of his twenty-three year career in German intelligence, including twelve years in the service of the Nazi regime, it is unlikely that
he would have felt a need to hide a short intelligence assignment in the Middle East.
Furthermore, given the political confusion that wracked Germany in the months
immediately following the armistice of November 1918, it is difficult to imagine what
German foreign intelligence agency remained sufficiently operational to run agents
into the Middle East at the time of Fenner’s alleged arrest.
It is clear that by February 1920, Fenner had left the Free Corps and returned to
civilian life, where he took a job as a publicist with an émigré assistance organization. As a career move it was a mistake. The press expressed little interest in the articles he attempted to place, and within a year, he was looking for a new job.
Eventually he found a position as an editor in a fledgling press agency, founded
by Konstantin von Krusenstern (a former colonel in the Imperial Russian Army,
who like many of his compatriots had fled to Germany after the Bolshevik Revolution). Any hope of a career in journalism that Fenner may have retained was
dashed when the press agency’s finances collapsed and Krusenstern found it convenient to relocate immediately to Paris. Before departing for greener (or at least
safer) pastures, the erstwhile Russian colonel introduced his now unemployed editor
to Peter Novopaschenny, another expatriate Russian who had taught astronomy
before joining the Tsarist navy’s cryptanalytic service during the recent war. Novopaschenny was also unemployed and searching for a professional and financial niche
in postwar Berlin. At their first meeting, the sometime astronomer and the aspiring
journalist could hardly have imagined that their association would lead to professional success and (at least in Fenner’s case) political power that could never be
duplicated in a classroom or newspaper office.
Introduction to Comint
Novopaschenny hoped to parlay his codebreaking experience into a job with the
small military establishment permitted to Germany under the terms of the Treaty
of Versailles, and he asked his new German friend to help him make the appropriate
contacts. Fenner readily agreed, and in the course of approaching various officers he
Wilhelm Fenner
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made the acquaintance of Erich Buschenhagen, a wartime lieutenant in radio
intelligence, who had contributed his experience to the Free Corps by establishing
in early 1919 a Volunteer Evaluation Post. Initially, this unit collected plaintext
material from various sources, including the press, but rather quickly it recruited several cryptanalysts who began working on Russian military communications. By the
time that Fenner encountered Buschenhagen, the Volunteer Evaluation Post had
been absorbed into Germany’s small postwar military establishment as the Cipher
Bureau in the intelligence branch of the army’s Troops Department, the rump general staff allowed Germany under the terms of the peace agreement [12, p. 191].
Since his cryptanalytic staff focused primarily on Russian systems, Buschenhagen
jumped at an offer of services from one of the Tsar’s former codebreakers. In fact, the
director of the Cipher Bureau was probably more interested in Novopaschenny than
in his German friend. At this time, Fenner was the first to admit that he knew nothing
about cryptology. His interest was piqued, however, by the encrypted Russian telegrams
that Novopaschenny, working out of his apartment, began to study for the Cipher
Bureau. Together the two friends labored on the messages, Novopaschenny teaching
Fenner the methods of cryptanalysis and Fenner contributing his superior knowledge
of the German language to the process of translation. The collaboration proved fruitful;
within a few weeks, the two friends had cracked their first Russian cipher.
Erich Buschenhagen was impressed by the success of the FennerNovopaschenny team, the more so since the Cipher Bureau’s four-person Russian
section seemed to have been flummoxed by the same cipher the two outsiders had
solved. In the fall of 1922, Buschenhagen officially hired the two and took the unexpected step of placing Fenner in charge of the Bureau’s cryptanalytic section. The
appointment said much for Buschenhagen’s confidence in Fenner, who to no one’s
greater surprise than his own was demonstrating a native appetite and talent for
codebreaking. It also said much for the rather mediocre state of cryptanalysis in
the Cipher Bureau.
When Wilhelm Fenner took up his new post in the Defense Ministry building on
Berlin’s Bendlerstrasse, he directed an office of eleven people who tried to solve
foreign diplomatic and military cryptosystems. Two analysts worked on British codes;
one analyst studied French systems; another attacked Italian systems; and six (including Fenner and Novopaschenny) were assigned to Russian codes. A statistician
rounded out the group. The new director was decidedly unimpressed by his team.
In practice the office worked only on unenciphered diplomatic codes—a focus which
the new director believed too narrow and conservative. Output was modest with the
codebreakers happy to decrypt three or four messages a day. More serious, at least
in Fenner’s eyes, were the lax work habits of the office and an organizational culture
that prized ‘‘genius’’ and inspiration over system and method as the key to cryptanalytic success. The approach was so amateurish that the codebreakers did not even
share a common technical vocabulary, so that the British desk would describe systems
and methods of solution in terms different from those used by the Russian desk. In its
work habits, the Cipher Bureau seemed a throwback to the Black Chambers of the seventeenth and eighteenth centuries; Fenner set out to drag it into the twentieth century.
Building the Cipher Bureau
As the first step toward modernizing and professionalizing the Cipher Bureau’s crypanalytic section, the new director instituted a program of formal training. To
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prepare such a program, Fenner first collected and reviewed the surviving reports
from Germany’s wartime codebreaking units and studied the works on cryptology
available in German military libraries. He then set for his staff a series of standard
cryptanalytic problems, few of which they could solve. Their failure came as no surprise to Fenner, who was oblivious (or indifferent) to the possibility that such exercises might not endear him to his staff. Having demonstrated his staff’s inadequacy,
Fenner instituted for all personnel a series of lectures (which he insisted on delivering
personally) that set out the general characteristics of the various types of systems,
and the methods of solving each type. To improve work habits, he personally
reviewed all reports, ruthlessly editing them for clarity and logic and insisting that
the desks adhere to a common format and vocabulary. Not surprisingly, the reforms
were not embraced by all the staff, and it was probably at this time that the director
acquired his reputation of an arrogant, self-important pedant, but Fenner considered
the reaction evidence that the unit was being shaken out of its lethargy and complacency. He dismissed the complaints [7, p. 32].
Training became a fetish for Fenner, and throughout his career, even after the
demands of administration distanced him from operational cryptanalysis, he remained
personally engaged in the professional education of his staff. Concerned that codebreakers working the same cryptanalytic target for years would become stale and so
lose touch with developments in the field that they felt adrift when transferred to
another problem or when ‘‘their’’ system was replaced by a new code or cipher, Fenner
in the mid-1920s created a 90-day course for senior analysts that reviewed general principles and current systems. In the early 1930s he instituted for talented younger staff a
two-part course on cryptologic principles and practice that met twice a week in his
office. Only during the Second World War, when administrative burdens became too
onerous, did Fenner transfer some of the teaching load to assistants [7, p. 33].
For Wilhelm Fenner, training was only part of an effort to professionalize his
service. When he joined the Cipher Bureau, the employees, whose arcane skills did
not fit into any of the established job categories or ranks of the hierarchical German
bureaucracy, were not considered career civil servants and so had neither job security
nor pension rights. Convinced that an individual was more likely to serve the
state loyally and fully if that individual believed that the state had an equivalent
commitment to his well-being, Fenner worked conscientiously to secure official recognition and status for his staff. Such recognition would provide a formal career
path for employees with regulations governing requirements for entry (university
degree and examinations to demonstrate linguistic or mathematical aptitude), a probationary period, promotion after further exams, and most importantly pension
rights. The struggle for professional recognition and security for his codebreakers
was long and arduous; Fenner began agitating on behalf of this goal in the 1920s
but did not see success until shortly before the outbreak of the Second World
War in 1939 [7, p. 34].
While central to his vision of a modern communications intelligence service, professionalism was for Fenner always a means to a larger end. The Cipher Bureau was,
after all, not a school or a bureaucratic sinecure, but an intelligence service. And, a
few mediocre analysts, slowly reconstructing a half dozen foreign codes and producing (at their best) a handful of translations a week was not what Wilhelm Fenner had
in mind when he thought of an intelligence service. Rigorous recruitment, promotion, and retention practices combined with serious training improved capabilities, but improved production also required an expansion in operations.
Wilhelm Fenner
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Under Fenner’s aggressive command the cryptanalytic section went on the
offensive. By 1924, Poland and Romania had joined Britain, France, Italy, and
the Soviet Union on the target list, and by 1926, the list had further grown to include
Czechoslovakia and the United States. By the spring of the latter year, a mere four
years after Fenner’s arrival, the revitalized Cipher Bureau had identified in the intercepted traffic 85 different codes and ciphers. The Bureau had attacked twenty-two of
these systems and solved sixteen of them (six in the first quarter of 1926), including
high-grade French and Italian diplomatic systems and three Czech army systems.
More aggressive operations, however, did not automatically translate into more successes, and the codebreakers’ record remained uneven. Russian diplomatic systems,
for example, resisted every attack, although a simple Red Army field code was
solved. Polish diplomatic systems also remained impenetrable except for a code used
by Polish consuls [5, pp. 5–8].
The problem was, in large part, an insufficient number of competent
analysts. Additional personnel had been recruited and the roster of the cryptanalytic
section now approached thirty, but the newcomers remained unseasoned, while
some of the veterans were suited only for the more simple and routine cryptanalytic
tasks. As the Cipher Bureau’s report for the first quarter of 1926 emphasized, ‘‘The
number of independent deciphers—compared to the number of employees in
general—is relatively small’’ [5, p. 9]. Fenner addressed this problem by combining
his best analysts into temporary working groups to attack a particular problem.
The solution in early 1926, of France’s new high grade diplomatic system, was the
work of such a group composed of eleven staffers. While mobilizing the best minds
in the small organization against an important target, Fenner’s approach had
the disadvantage of retarding work against systems deemed less important. Thus,
allowing the cryptanalytic section to focus on the Quai d’Orsay’s new system, put
work against Polish diplomatic and military attaché ciphers on the back burner [5,
pp. 5, 9].
The capabilities of the Cipher Bureau continued to increase as the unit moved
into the 1930s. By the end of 1932, the bureau had solved more than forty foreign
cryptosystems. That year Fenner’s team was reading two Polish diplomatic systems
as well as a cipher used by Polish military attaches, two Italian diplomatic systems
and at least one Italian military system, several French diplomatic codes as well as
systems used by the French army in Algeria and the French air force, a British diplomatic code and a system used by London to communicate with government offices in
the empire, two American diplomatic codes (the GRAY and GREEN codes), at least
two Czech army codes, and several codes used by the collective farms administration
in the Soviet Union. Successes (though of indeterminable extent) seem to have
been registered also against Belgian, Romanian, and Yugoslavian cryptosystems
[6, pp. 8ff; 4, p. 31].
The growing capabilities of the Cipher Bureau were further enhanced by contacts with foreign services. Fenner’s role in the early exchanges remains uncertain.
Some time in early 1923, Lieutenant Buschenhagen visited Vienna in the hope of
opening conversations with the Austrian Cipher Bureau. The Austrians, who could
trace the cryptanalytic lineage of their service back two centuries, may have been
unimpressed by the unseasoned neophytes in Berlin for they rejected the approach.
Word of the German initiative, however, reached Budapest where the Hungarian
Cipher Bureau was not too proud to seek collaborators. In the autumn of 1923,
Colonel Wilhelm Kabina, chief of the Hungarian service, traveled to Berlin and
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quickly negotiated an arrangement in which the two cryptanalytic services would
collaborate against Italian codes and ciphers. This agreement was later extended
to other cryptanalytic targets [9, pp. 1–2].
The arrangement with Hungary was the first in a string of liaison agreements
with other countries. Within a year, the Austrians had second thoughts about their
aloofness and sent a delegation to Berlin to establish a working relationship. In 1927,
Finland established a cryptanalytic service and its first director, Major Reino Hallamaa, traveled to Berlin to observe the methods of the Cipher Bureau and secure its
assistance. In June of that year, Fenner went to Finland to deliver a course of
instruction to the members of the fledgling service. By the end of the decade, the
two services were actively collaborating against Soviet cryptanalytic targets. The list
of foreign partners expanded further in the 1930s, with more or less formal arrangements with Italy (against France), Franco’s Nationalists during the Spanish Civil
War (against Spanish Republicans and France), and Estonia (against the Soviet
Union), [9, pp. 3–5, 13–14].
Fighting Off Rivals: Pers Z
There is no better evidence of the growing stature of the Cipher Bureau than the
reaction of its competitors. At the end of the First World War, the German foreign
ministry had organized its own cryptanalytic service, and by the spring of 1919 this
service employed more than fifty men and women [2, p. 3; 1, pp. 169–170]. The ministry’s codebreakers focused exclusively on foreign diplomatic codes and ciphers, and
as the larger and more senior service they considered Fenner’s group an unwelcome
interloper. Their disquiet increased as the Cipher Bureau began to expand its program of diplomatic cryptanalysis. To solidify its position, the foreign ministry protested that the armed forces (the Cipher Bureau was at this time still attached to the
army) should limit their communications intelligence activities to the study of foreign
military codes and ciphers and eschew any effort in the area of diplomatic systems
[10, pp. 5–6].
The hostility of the foreign ministry and its claim to monopolize diplomatic
communications intelligence was no small matter. A cryptanalytic service is only
as strong as its ability to intercept foreign messages for study, solution and translation. At this time (1925–26), the Cipher Bureau received messages from a network
of seven army radio monitoring stations scattered along the periphery of Germany.
Only one of these stations (Treuenbrietzen outside of Berlin) focused on diplomatic
traffic; the remainder intercepted primarily military traffic. To secure sufficient
diplomatic messages for cryptanalysis, the Cipher Bureau needed access to the
foreign traffic that passed through channels controlled by the German Post Office.
In the 1920s, for example, embassies in Berlin did not have direct and independent
radio communications with their foreign ministries, but relied on the German Post
Office to transmit and receive their encrypted messages. The postal service routinely
retained copies of all such embassy messages and passed them to the codebreakers
for study. Unfortunately for the Cipher Bureau, the post office dealt only with the
foreign ministry and refused to give diplomatic cablegrams to the military. To maintain a flow of intercepted messages adequate to feed the appetite of his growing
office, Fenner needed access to those post office messages.
Within the organizational structure of the Cipher Bureau, Wilhelm Fenner was
still only the chief of the cryptanalytic section, but after the departure of Erich
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Buschenhagen in 1925 and his replacement as Bureau director by a series of career
army officers who for the most part knew little about communications intelligence,
Fenner, by experience, ability and force of character became the de facto head of the
service. It was left to him, therefore, to deflect the assault from the foreign ministry.
Fenner countered the ministry’s protest by deprecating the distinction between diplomatic and military communications. He argued that in peace time diplomatic communications often included information of military interest, and military analysts
were more likely to identify such items in messages and understand their significance.
He also pointed out that his agency required continuous access to current diplomatic
ciphers in order to maintain and expand its cryptanalytic skills. If required to focus
only on the relatively simple peace time ciphers in service in most European armies,
the skills of the Cipher Bureau would atrophy and the service would be poorly prepared to serve Germany in future international crises.
Although after the Second World War certain of Fenner’s colleagues would
remember him as somewhat arrogant and lacking in tact, he seemed to have defused
the opposition of the foreign office with some dexterity. He convinced his opposite
number in the foreign ministry, Kurt Selchow, that cooperation would benefit both
units. Specifically, he promised Selchow that as the military expanded and improved
its radio monitoring network the foreign ministry codebreakers would have access to
all diplomatic messages intercepted. Fenner also offered to share the Cipher Bureau’s
cryptanalytic materials and results [10, p. 17]. The result of Fenner’s diplomacy was a
degree of inter-agency collaboration that was rare in the normally hostile and competitive German intelligence community. Over the years, the cooperation expanded,
so that by the Second World War the two agencies were not only sharing the results
of their cryptanalytic work, but were also exchanging personnel [2, pp. 49–51; 10, p.
17]. Unfortunately for Fenner (and for Germany), relations with other agencies
would not be so smooth.
Fighting Off Rivals: Forschungsamt
The rise of the Nazis in the early 1930s created more intractable problems for Fenner
and the Cipher Bureau, which in 1928 had been moved from the army command to
the war ministry. Some of the problems involved personnel; cryptanalysts were no
more immune to the blandishments of Adolf Hitler and his vision of a renewed Reich
than were postmen, grocers, or university professors. Within the Cipher Bureau a
small circle of Nazi-sympathizers became increasingly vocal. Fenner, whose own
political sympathies are hard to discern in the available evidence, had little patience
with these employees who constantly talked politics at their work tables or during
extended coffee breaks in the office snack bar, flaunted their loyalties by smoking
Nazi Party cigarettes, pressured their colleagues for donations to funds for the relief
of injured or distressed members of the Sturmabteilungen, the Party’s brown-shirted,
strong- arm squads, and forsook work entirely to participate in a ‘‘Jew raid.’’ If
Fenner was not offended by the new political attitudes, he was certainly upset by
the disruption of work routines and by the negative impact of the militants on the
morale, collegiality, and professionalism of his office [10, p. 16].
The atmosphere worsened after the Nazi assumption of power in early 1933,
and not just because Hitler’s admirers inside the Cipher Bureau were emboldened.
Although Fenner, in most cases, was still able to recruit individuals who were
not members of the Nazi Party, he worried about a decline in the independence and
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professionalism of his agency as the Party and its satraps tried to extend their control
over the intelligence and security agencies of the state. His fears were confirmed in the
spring of 1933, when with the connivance of disgruntled members of the Cipher Bureau
a new agency appeared to claim preeminence in communications intelligence.
In early 1933, several stalwarts of the Nazi clique inside the Cipher Bureau
resigned. To explain their departure these individuals alleged that they could no
longer endure the ‘‘incompetence’’ of the Bureau, but they were motivated more
by personal grievance than professional pride. Their ostensible leader was Emil
Freiherr von Reznicek, a codebreaker assigned to the Italian desk. Fenner, who
was his boss, considered him ‘‘an extremely able cryptanalyst with an undeniable
genius,’’ but Reznicek, an ardent Nazi, had become increasingly disaffected by what
he considered his inferior status inside the Cipher Bureau. He was particularly
annoyed that in the caste conscious world of the German bureaucracy he remained
a mere ‘‘employee’’ of the Bureau without pension rights while Fenner held the prestigious rank of Government Councillor [10, p. 17]. Another member of the cabal was
Gottfried Schapper, a radio intelligence veteran of the First War World who had
joined the Nazi Party in 1920 and the SS in 1933. In the Cipher Bureau, he ran a
small unit concerned with the location and construction of intercept sites. ‘‘[A]t heart
one of the most discontented’’, Schapper resented his lack of rank and status within
the Cipher Bureau [10, p. 17]. Lieutenant Commander Hans Schimpf, an active duty
naval officer who was the liaison with the German navy’s small cryptologic service
and deputy to the overall director of the Cipher Bureau, was another malcontent.
Considered by Fenner the real leader of the group, Schimpf was an ambitious schemer who, if office rumors were to be believed, covered all his bridges by paying dues
to both the Nazi Party and the German Communist Party.
Even before the resignations of the malcontents, Schimpf had (without Fenner’s
knowledge) contacted Hermann Göring, the newly designated aviation minister in
Hitler’s government, and suggested the creation of a new communications intelligence agency that would centralize all aspects of communications intelligence from
phone intercepts to cryptanalysis of foreign diplomatic messages. Göring saw in
the proposal an opportunity to enhance his position in the constant jockeying for
personal advantage that passed for high politics in the new regime. He authorized
the creation of a ‘‘Research Office’’ (Forschungsamt, though generally known simply
as the FA) subordinated directly to his person, not to any ministry of the government, although for cover purposes the office was nominally attached to the aviation
ministry. Lieutenant Commander Hans Schimpf resigned from the navy as well as
from the Cipher Bureau to become the first chief of the new agency.2 In his flight
to the Forschungsamt, he was joined by Gottfried Schapper who became Schimpf’s
deputy for administration, Emil Reznecik, and seven other employees of the Cipher
Bureau, including the chief of the intercept service and cryptanalysts from Fenner’s
British, French, and Polish desks [10, p. 14; 3, p. 10].
Fenner may well have been glad to see the malcontents go, but he quickly discovered that he was not entirely rid of them. From either a desire to revenge themselves on their former employer or an organizational impulse to expand their
2
During his postwar interrogation, Walther Seifert, a Cipher Bureau staffer who defected
to the Forschungsamt with Schapper and Schimpf and eventually rose to direct the FA’s
evaluation section, testified that Schimpf (who committed suicide in 1935) should receive
credit for initiating the new agency [3, p. 10].
Wilhelm Fenner
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agency’s ‘‘turf’’ (or both), Schimpf and Schapper promptly notified the Cipher
Bureau that the Forschungsamt was now solely responsible for all diplomatic cryptanalysis and that Fenner’s codebreakers should immediately abandon such work.
This was a repeat of the earlier contest with the foreign ministry’s cryptanalytic section, and Fenner deployed many of the same arguments that had served to turn back
the earlier threat. Ironically, in the latest bureaucratic battle he found an ally in his
former nemesis Kurt Selchow who realized that, if successfully prosecuted, the FA’s
claim to a monopoly on diplomatic cryptanalysis would also mean the end of his
foreign ministry unit [10, p. 10].
In the end, Fenner managed to fend off the threat from the Forschungsamt and
retain for the Cipher Bureau a role in diplomatic cryptanalysis, but the relationship
between the two agencies remained cool and distrustful, and there was never any
effort at cryptanalytic collaboration. For his part, Fenner was even less inclined to
bury the hatchet when he discovered that his former subordinates now ensconced
in senior positions in the FA had started a campaign to have him relieved of his position in the Cipher Bureau and that this campaign included tapping his office phone,
planting an informant in his office, and spreading rumors that he was Jewish and
had ridiculed and criticized Göring in private conversations [10, p. 11].
The arena of German communications intelligence was becoming crowded and
Fenner found it increasingly difficult to fend off competitors. The German navy had
established a cryptanalytic service during the First World War, but its codebreakers
focused exclusively on foreign naval codes and ciphers and posed no threat to the
Cipher Bureau. More serious was the appearance in the mid-30s of separate
codebreaking agencies in the German army and air force. The army had developed
a radio intelligence service during the war, but in the peacetime demobilization had
been content to cede the field to the Cipher Bureau. Fenner actively opposed the
reappearance of a separate army service, but he could not block the creation in
1934 of the ‘‘Intercept Control Station,’’ the nucleus of an agency that took over
the Cipher Bureau’s responsibility for interception and analysis of the communications of foreign armies. The appearance in 1937 of an air force signal intelligence service introduced another player in the increasingly stiff competition for missions,
money, and manpower. Though the Cipher Bureau was now explicitly prohibited
from engaging in any military cryptanalysis, Fenner chose the path of passive resistance. For example, convinced that neither the army nor the air force services had
sufficient experience or expertise to cover the communications of the Red Army
and Air Force, Fenner disobeyed orders and secretly directed some of his personnel
to continue their work on Russian military systems. A covert party of Cipher Bureau
codebreakers may also have continued to attack French army ciphers. Fenner’s
instincts proved sound. When war broke out in 1939, both the army and air force
services were overwhelmed by the demands from their services for decryptions,
and in desperation they appealed to the Cipher Bureau (by then known as
OKW=Chi after a reorganization in 1938 that made it the Chiffrierabteilung of the
Armed Forces High Command) for expert assistance on French systems, an appeal
that would be repeated in 1941 when Germany attacked the Soviet Union.
Conclusion
By the eve of the Second World War, OKW=Chi had a staff of almost two hundred
men and women, not including personnel who worked in the intercept stations. In
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1922, when Wilhelm Fenner had assumed command of the Cipher Bureau’s cryptanalytic section, fewer than a dozen analysts struggled against the codes and ciphers
of just four countries: Britain, France, Italy, and Russia. In 1939, Fenner, still in
command, directed the work of more than eighty cryptanalysts who were attacking
the cryptosystems of more than twenty countries, including Belgium, Britain,
France, Italy, the Netherlands, Poland, Romania, Russia, Spain, Switzerland,
Turkey, the United States, the Vatican, and Yugoslavia. In 1939, the staff of the
Russian desk (still headed by Fenner’s old mentor, Peter Novopaschenny) alone
exceeded the roster of the entire cryptanalytic section in 1922 [11, n.p.]. With the
exception of Britain’s Government Code and Cypher School, and perhaps, its
Russian equivalent (about which historians still know very little), no foreign cryptanalytic service could match the reach of Fenner’s unit as Europe approached the
precipice of war. Few, furthermore could match its professionalism.
Fenner’s importance in the history of German intelligence is not just that he presided over the expansion of the Cipher Bureau in the interwar years. As the effective
head of the Cipher Bureau for most of that period, he was able to mold the organization’s culture, as well as it size. His emphasis on selective recruitment, continuous
training, merit promotions, and insulation from political interference reflected his
commitment to creating a professional service. His resistance to the proliferation
of new communications intelligence units, such as the Forschungsamt and the codebreaking agencies of the army and air force, was based not only on the protection of
his organization’s ‘‘turf’’, but on an understanding that by dispersing the limited
number of able personnel and other scarce resources and fostering inter-agency suspicions the new agencies would not improve but undercut Germany’s cryptanalytic
capabilities. Germany’s codebreaking experience in the Second World War, characterized by duplication of effort, understaffing, inadequate technical resources, and
uncoordinated operations, suggests that in this as in so many other matters Wilhelm
Fenner stood head and shoulders above his contemporaries in German communications intelligence.
About the Author
A former scholar-in-residence at the National Security Agency, David Alvarez teaches intelligence history at Saint Mary’s College of California. He is the author of
Secret Messages: Codebreaking and American Diplomacy, 1930–1945 (2000) and
the editor of ALLIED AND AXIS SIGNALS INTELLIGENCE IN WORLD
WAR II (1999).
References
1. Alvarez, D. ‘‘Diplomatic Solutions: German Foreign Office Cryptanalysis, 1919–1945,’’
Summer, 1996. International Journal of Intelligence and Counterintelligence, 9(2):169–185.
2. Army Security Agency. European Axis Signal Intelligence in World War II, vol. 6: Foreign
Office Cryptanalytic Section. 1946. National Security Agency. Freedom of Information
Act., Washington D.C.
3. Army Security Agency. European Axis Signal Intelligence in World War II, vol. 7:
Goering’s Research Bureau. 1946. National Security Agency. Freedom of Information
Act., Washington, D.C.
4. Chapman, J. W. M. 1986. ‘‘No Final Solution: A Survey of the Cryptanalytic Capabilities
of German Military Agencies, 1926–35,’’ Intelligence and National Security, 1(1):13–47.
Wilhelm Fenner
163
5. Cipher Bureau. First Quarterly Report for 1926, Bundesarchiv-Militärarchiv, RH 67=RW
5=702.
6. Cipher Bureau. Fourth Quarterly Report for 1932, Bundesarchiv-Militärarchiv, RH
67=RW 5=728.
7. Extracts from Homework Written by Min. Rat Wilhelm Fenner of OKW=Chi. 7 August
1947. TICOM=I-206. National Security Agency. Freedom of Information Act.
8. Fenner, W. 1949. The Career of Wilhelm Fenner with Special Regard to His Activity in
the Field of Cryptography and Cryptanalysis, DF–187, Army Security Agency. National
Security Agency. Freedom of Information Act.
9. Fenner, W. 1949. Relations of OKW=Chi with foreign cryptologic bureaux, DF-187D.
Army Security Agency. National Security Agency. Freedom of Information Act.
10. Fenner, W. 1949. Relations of OKW=Chi with other German Cryptologic Bureaux,
DF-187C. Army Security Agency. National Security Agency. Freedom of Information Act.
11. Fenner, W. 1949. Organization of the Cryptologic Agency of the Armed Forces High
Command, with Names, Activities, and Number of Employees Together with a Description of the Devices Used, DF-187A. Army Security Agency. National Security Agency.
Freedom of Information Act.
12. Kahn, D. 1978. Hitler’s Spies: German Military Intelligence in World War II. New York:
Macmillan.