During WWII the British foreign intelligence service benefitted from the successes of Bletchley Park versus Axis military, diplomatic and agents codes. Similarly the German foreign intelligence services received summary reports from the Signal Intelligence Agency of the Supreme Command of the Armed Forces - OKW/Chi (Oberkommando der Wehrmacht/Chiffrier Abteilung).The Sicherheitsdienst was the security service of the SS and its foreign intelligence department Amt VI (headed by General Walter Schellenberg) had some notable successes during the war. According to Schellenberg and two high-ranking SD officials their agency received daily reports from OKW/Chi, containing important diplomatic messages from Bern, Ankara, Algiers, Moscow and other areas.
Since it seems that most of the OKW/Chi archives were destroyed or lost at the end of WWII these statements are important in evaluating the successes or failures of that organization.
1). General Schellenberg was interrogated postwar by the Allies and in ‘Report on interrogation of Walter Schellenberg 27 June- 12 July 1945’, p30 he said:
The Germans broke the American code. Messages sent by HARRISON, U.S.A. minister in Berne, to Washington, lay daily deciphered on SCHELLENBERG's desk. These messages sometimes contained intelligence service material. SCHELLENBERG also received Turkish, Polish, French, Swiss, South American, Spanish and Portuguese messages which were all decoded.
2). SS-Sturmbannführer Dr. Klaus Huegel was an important SD official with knowledge of German spy activities in Switzerland and Italy. In one of his postwar interrogations he mentioned that from April 1943 to March 1944 he had access to the daily reports sent from OKW/Chi to General Schellenberg. The reports often included US diplomatic messages from Bern, Switzerland, British messages from the Bern embassy, De Gaulle traffic from Algiers to Washington and messages from the Turkish ambassador in Moscow.
3). Giselher Wirsing was an accomplished author and journalist, who in 1944 joined the SD foreign intelligence department as an evaluator. Wirsing had come to the attention of General Schellenberg due to his clear headed analysis of the global political situation and of Germany’s poor outlook for the future. Under Schellenberg’s protection he wrote a series of objective reports (called Egmont berichte) showing that Germany was losing the war and thus a political solution would have to be found to avoid total defeat. While writing his reports Wirsing had access to the OKW/Chi summaries sent to the SD leadership. According to him the messages ‘did not reveal any startling news‘ but were useful in assessing information from other sources. He remembered messages from the US, Japanese, Turkish and Bulgarian ambassadors in Moscow, State Department messages to Paris, traffic from the US mission in the Balkans and messages from the Polish mission in Jerusalem to their London based goverment in exile.
Overall it is clear that OKW/Chi provided valuable information to the Sicherheitsdienst leadership, even though they served different masters (OKW/Chi was subordinated to the military while the Sicherheitsdienst came under the control of the Nazi party).
Sources: CIA FOIA reports HUEGEL, KLAUS No 22 and WIRSING, GISELHER No 16,
British national archives KV 2/95 ‘Walter Friedrich SCHELLENBERG: rose to be No. 2 in the S.D. and was close to Himmler’