Mallmann Showell, Jak P. German Naval Code Breakers

Mallmann Showell, Jak P. German Naval Code Breakers

Dale C. Rielage

Mallmann Showell, Jak P. German Naval Codebreakers. Annapolis, Md.: Naval Institute Press, 2003. 160pp. $29.95

In the almost thirty years since the public revelation that the Allies in World War II broke substantial portions of the German ENIGMA cipher system, Allied codebreaking has become a staple of our understanding of the Battle of the Atlantic. Less understood are the parallel efforts of the German navy to break Allied naval codes. The historical record of German codebreaking is comparatively fragmentary, many records having been destroyed during or immediately after the war. German naval intelligence was smaller than its Allied counterparts and left a smaller trace. Still, the influence of these German efforts on the pivotal convoy battles of the war has remained an important unanswered question. In German Naval Codebreakers, Jak Showell, author of more than a dozen books on German U-boats, has attempted to provide an account of signals intelligence in the German navy in World War II.

The German Naval Radio Monitoring Service (or Funkbeobachtungsdienst, commonly abbreviated B-Dienst) worked with some success against British and American naval codes. During the early period of the war until 1943, the B-Dienst could read large parts of the Allied merchant ship and convoy codes, which provided important insights into convoy operations and routing. In addition to codebreaking, B-Dienst operated a network of direction finders that fixed the approximate locations of radio transmissions in the Atlantic.

Whatever its success at codebreaking, the German navy in World War II failed at the critical second step of intelligence analysis. Showell creates the impression that B-Dienst personnel were separated from key operational commanders and were not permitted access to information about their own forces’ operations. The B-Dienst was therefore reduced to passing raw messages to senior commands, feeding the complaint that radio intelligence served only to provide a flood of useless information. This arrangement stands in marked contrast to the intimate relationship between commanders and operational intelligence centers in Britain and the United States.

From the outset, the book suffers from an unfortunate organization. Attempting to avoid a chronological history of the war at sea, the author has arranged his material in a series of short vignettes, separated by ship type and area of operations. Lost in this organization is the common thread of the B-Dienst itself. Showell, for example, touches on the question of how intelligence support was provided to German units at sea in several sections but never ties them together to address the critical question of information dissemination across the German navy. Showell attempts to circumvent this problem by a series of appendixes on organization, but these are too brief to serve the need, and the result is confusing and unclear.

Within these sections there are historical gems. For example, the author discusses a February 1943 incident in which the B-Dienst intercepted a British message containing German submarine locations–potential evidence that the German code was itself being read by the Allies. Ultimately, the German navy convinced itself that its operational information had been compromised through other means and that its codes were secure. However, this gem, like all others mentioned, suffers from the second major failing of the book–an almost complete lack of documentation. While the work contains a list of recommended reading and mentions at the outset that it is largely based on work found in private archives in Germany, there is no further reference to the evidence.

The third and perhaps most important failing of the book is a failure to explore the full implications of German successes and failures. The fundamental historical question is how the German navy set out to provide intelligence information to its commanders, and how and why it succeeded or failed in that effort. That question is never answered, leaving the book at best titillating but unsatisfying.

Dale C. Rielage

Lieutenant Commander, U.S. Navy

Assistant Naval Attache, Berlin

COPYRIGHT 2006 U.S. Naval War College

COPYRIGHT 2008 Gale, Cengage Learning