Collection ULTRA 1-139 - ULTRA: decoded German signals, 1941-1945

Key Information

Reference code

ULTRA 1-139

Title

ULTRA: decoded German signals, 1941-1945

Date(s)

  • 1941-1945 (Creation)

Level of description

Collection

Extent

139 reels

Scope and content

ULTRA: British Intelligence Messages based on decoded German Signals, 1941-1945 is a microfilm copy of file copies of decrypted teleprinter messages held at the National Archives, Kew (DEFE 3), relating to operational intelligence from intercepted German and Italian radio communications, 1941-1945. These signals became known as ULTRA. The various series of the messages are of two distinct types: intercepted signals, decrypted, translated, and sent from the German Naval Section of the Admiralty's Naval Intelligence Centre in the Admiralty; and summaries of intelligence derived from such signals sent to the War Office, Air Ministry, and overseas commands. The collection includes translated messages relating to the German invasion of Yugoslavia, Greece, Apr 1941; forewarnings of the impending German invasion of Crete, May 1941; Operation CRUSADER, 8 Army operations in the Western Desert, Nov 1941-Jan 1942; German Air Force cover of Mediterranean transport operations, Nov 1941-Jan 1942; forewarnings of the advance in the Western Desert of German Armed Forces under the command of Col Gen Erwin Rommel, Aug 1941; German surface vessel and U-boat communications, Aug 1941-Feb 1942; Allied victory over German U-boats in the Atlantic, 1942-1943; the delay of 8 Army, under the command of Gen Bernard Law Montgomery, at Mersa el Brega, Libya, Dec 1942; the Allied campaign in Sicily, Jul 1943; the Italian surrender and the Allied landing in Italy, Sep 1943; Adolf Hitler's decision to stand on successive defensive lines in Italy, Oct 1943; forewarning of FM Albert Kesselring's decision not to advance beyond his attack at Anzio, Italy, Feb 1944; and collected intercepts which identified the German divisions manning the coastal defences in the Pas de Calais, France, Jun 1944.

System of arrangement

Arranged into series according to source of decryption and subject matter, and chronologically therein. For example, the first series relates to intelligence from enemy radio communications, Mar 1941-Apr 1945; the second series are decrypted German signals, Mar 1941-May 1945, which includes teleprinted translations of decrypted messages; the third series are Allied intelligence messages based on intercepted signals, Jul 1942-May 1945. All series in the microfilm collection have corresponding National Archives (DEFE 3) reference numbers.

General Information

Custodial history

The National Archives, Kew, Surrey

Conditions governing access

Open, subject to signature of Reader's undertaking form, and appropriate provision of two forms of identification, to include one photographic ID.

Conditions governing reproduction

Copies may be printed off the microfilm/microfiche for research purposes and are charged at cost.

Enquiries concerning the copyright of the original material should be addressed to The National Archives

Language of material

Script of material

Finding aids

This collection level description. Further finding aids may be available in the Reading Room.

Existence and location of originals

Off-campus collection

Please note: We require 7 days notice to retrieve this collection as part, or all of it, is held off-campus. Read more ›

The National Archives, Kew, Surrey

Existence and location of copies

National Archives and Record Administration, Washington, DC.

Related descriptions

Note

Compiled Oct 1999

Alternative identifier(s)

Subjects

Place access points

People and Organisations

Genre access points

Rules and/or conventions used

Compiled in compliance with General International Standard Archival Description, ISAD(G), second edition, 2000.

Script(s)

Accession area

Related subjects

Related people and organisations

Related genres

Related places