The Influence of ULTRA on World War II

Bruce Ediger

I read a paper, The Influence of ULTRA on World War II by Dr Harold C. Deutsch.

It was published in 1978, in Parameters, Journal of the US Army War College. It was Approved for public release; distribution unlimited

I read this paper because I read its companion piece, The Historical Impact of Revealing the Ultra Secret published in 1977. I’m not sure what the difference between “Influence” and “historical impact” amounts to.

I’m more convinced than ever that Neil Stephenson started with Deutsch’s two papers when writing Cryptonomicon. Deutsch abandons the wishy washy “only history can tell” angle on ULTRA decryption of essentially all of the German encrypted radio communications. In this article, ULTRA wins the war in Europe. Deutsch writes a lot about how ULTRA enabled the Double Cross System, and how ULTRA won the Battle of the Atlantic for the Allies.

I’m personally stunned by how many people were completely immersed in the war effort in the UK - Deutsch has about 10,000 people working at Bletchley Park deciphering Enigma machine messages. That number has to barely scratch the surface of the entire program. There had to be signals intelligence people listening for and copying Morse code radio transmissions, couriers, and others, as well as the military personnel directly involved in distributing the finished product to the field outside of that 10,000.

More about the author, Harold C Deutsch

Harold Deutsch’s Wikipedia article says:

In Europe he studied at the University of Paris, the University of Vienna and the University of Berlin.

In the 1920s-30s,this probably meant he could speak both French and German.

The wikipedia article doesn’t have much of a bibliography, but Deutsch apparently wrote several books about WW2.

  • Hitler and His Generals: The Hidden Crisis, January-June 1938, University of Minnesota Press, 1974. ISBN 978-0-8166-5744-5
  • The Conspiracy against Hitler in the Twilight War, University of Minnesota Press, 1968. ISBN 978-0-8166-5743-8
  • One of the online copies of blurbs about Hitler and His Generals indicates that Deutsch had yet another book about German resistance to Hitler in preparation. I can’t find any evidence of this book.

From the article:

The writer recalls a boast made to him in 1938 by the famed chief of German intelligence, Colonel Walter Nicolai.

An end note says that he interviewed Colonel Walter Nicolai at or about the same time period covered by Hitler and His Generals. Seems fishy. But it also explains Deutsch’s presence in the OSS during WW2. He knew, or at least had met, German intelligence people.

Two Instances on The Internet

As of 2025-04-17, you can find a PDF of this paper two places:

These are two different PDFs. Each one has a page the other doesn’t. The PDF from apps.dtic.mil has a Report Documentation Page Form, OMB No. 0704-0188 that does not appear in the Army War College PDF. The Army War College PDF has a title page listing the article as published in Parameters, the Army War College’s refereed journal. It does not appear in the apps.dtic.mil PDF, and it’s in far more modern typography.

These PDFs exhibit the same word spacing and letter spacing characteristics that an IBM Selectric Composer is said to produce.

Both PDFs appear to be scanned from paper copies. Pages 12 and 14 have black triangles at the top, typical of both xerox copies and scanned images made when the paper isn’t square on the scanner bed. The images of right hand side pages, in these PDFs, the odd-numbered pages, are slightly skewed. This, too, is common to scanned bound paper books and magazines. The binding prevents pages from lying completely flat.

At first, I thought these PDFs were independently scanned copies, but careful examination convinced me that there was some common PDF ancestral to both of them.

Official citation

Harold C. Deutsch, “THE INFLUENCE OF ULTRA ON WORLD WAR II,"
Parameters 8, no. 1 (1978),
doi:10.55540/0031-1723.1133.