Barbara Tuchman, in THE ZIMMERMAN TELEGRAM, speaks of the success of the British in breaking German naval codes during World War I. One major reason this happened is that the German Cruiser MADGEBURG, in October 1914, was set upon by 2 Russian Cruisers after she ran aground in a fog bank. The German Captain ordered some of his sailors to take the weighted bag containing the code book out in a row boat and to drop it into deep water. A Russian shell destroyed the rowboat, and, by a freak chance, the body of the sailor who was entrusted with the code book was recovered from the water, still clutching the code book in his arms. The Russians then passed the codes onto the British.
The dramatic jump this code book gave British cryptographers enabled them to start reading German naval code almost immediately. This would have dramatic impacts on the war at sea. The German strategy for dealing with the British Grand Fleet was to lure portions of it into positions where the entire German High Seas fleet could concentrate and destroy them, thus allowing the Germans to gradually defeat the British in detail. This was thwarted by signals intercepts, decoded because of the capture of the MADGEBURG codebook. For example, the German attempt to lure the British Battle Cruiser Squadron under Beatty to destruction at Dogger Bank was foiled because the British intercepted German wireless messages which lead Admiral Jellicoe to sally the entire fleet, rather than just the Battle Cruiser squadron. The same thing happened at Jutland.
But what if that sailor's body had never been recovered from the water, or if he had dropped the book into the sea in his dying moments, instead of clutching it to his chest? Or if the MADGEBURG had never run aground in the first place? The British never get the code book, and it takes them much longer to break the German codes, if indeed they ever do. The Germans are able to carry out their strategy at sea, luring detachments of British warships into traps where the superior numbers and gunnery of the Germans proves decisive. Finally, there is a showdown between the (now much reduced) British fleet and the main German fleet, where the Germans will have the advantages given to them by their superior optics and gunnery control systems. Assuming the Germans win that engagement...let's say it is in late 1916...how does this affect the course of the war?
The dramatic jump this code book gave British cryptographers enabled them to start reading German naval code almost immediately. This would have dramatic impacts on the war at sea. The German strategy for dealing with the British Grand Fleet was to lure portions of it into positions where the entire German High Seas fleet could concentrate and destroy them, thus allowing the Germans to gradually defeat the British in detail. This was thwarted by signals intercepts, decoded because of the capture of the MADGEBURG codebook. For example, the German attempt to lure the British Battle Cruiser Squadron under Beatty to destruction at Dogger Bank was foiled because the British intercepted German wireless messages which lead Admiral Jellicoe to sally the entire fleet, rather than just the Battle Cruiser squadron. The same thing happened at Jutland.
But what if that sailor's body had never been recovered from the water, or if he had dropped the book into the sea in his dying moments, instead of clutching it to his chest? Or if the MADGEBURG had never run aground in the first place? The British never get the code book, and it takes them much longer to break the German codes, if indeed they ever do. The Germans are able to carry out their strategy at sea, luring detachments of British warships into traps where the superior numbers and gunnery of the Germans proves decisive. Finally, there is a showdown between the (now much reduced) British fleet and the main German fleet, where the Germans will have the advantages given to them by their superior optics and gunnery control systems. Assuming the Germans win that engagement...let's say it is in late 1916...how does this affect the course of the war?