The Spanish Civil War

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Kriegsmarine U-boats and the Spanish Civil War

Historic writing varies about dating the official beginning of the Spanish Civil War. Several occasions are quoted, ranging from the win of the Parliamentary election of 26 February 1936 by the leftish “Popular Front”, or the military uprising on 22nd of July 1936, to the engagement of Army formations of the Spanish Forces in Marocco under General Francisco Franco on the Spanish mainland at the end of July 1936. This essay will not touch the further development up to the end of this struggle in Spring 1939 between the “Republicans” under the govern-ment in Spain (most prominent among its forces some 37,000 volunteers formed in “International Brigades”) and the “Nationalists” on the opposition side, massively supported by rebelling Army units. Also, the circumstances of the involvement of the German Reich and its support of Franco (official recognition of his “government” on 18 November 1936) as well as the deployment of units and formation of the Wehrmacht (= German Armed Forces) to Spain are taken for granted, and will not be discussed further.

It is widely known that Italy under Mussolini was determined in 1936 to support Franco by military means, among other forces were also U-boats. The German Reich followed and decided to grant Franco military support as well. According to corresponding reports some 16,000 t 17,000 soldiers of the Luftwaffe, Army and Kriegsmarine were detached in the end, well known the “Condor Legion” and the Battle Cruiser Deutschland.p283_1_00The German public became aware fully about the considerable engagement of the Wehrmacht in the Spanish Civil War not later than at the “Victory Parade” of the “Spanish Warriors” on 06 June 1939 in Berlin, including the participation of the Kriegsmarine through the marching formations of Naval personal. Among those were the crews of U 33 and U 34.

Therefore, the deployment of U-boats to the Atlantic and Mediterranean Sea areas was a rather special chapter in the history of the engagement of the Kriegsmarine during the years of the Spanish Civil War.


Summer 1938 – U 33 at El Ferrol

With that a chapter of the German Naval History has become public which has been surrounded by many myths, above all the first and “hot” deployment of two Kriegsmarine U-boats, since the actual involvement of the Kriegsmarine in the Spanish Civil War and the events particularly in the Mediterranean Sea off Spain has been declared “Secret” for a long time. So far, only a few authors have undertaken to research the few documents still available about the employment of the Kriegsmarine, which resulted in some differences with regard to delineating events, times and participants. Therefore, the low number of publications seems rather remarkable, most probably caused be the difficult situation with regard to resources available, as documents were often destroyed entirely, and, in the case of U 33 and U 34, eye witnesses of an U-boat deployment were obliged in writing to keep confidentiality under all circumstances, violations to that threatened by death penalty. Moreover, most of these eye witnessed have died meanwhile.

Also the German U-boat Museum has only very few documents about these deployments, by and large secondary literature only and a few statements of some eye witnesses. Therefore, the following essay is based mainly on literature and few documents still available.
However, that allows sufficiently painting a generally true picture of the events, to gain some idea about the employment of Kriegsmarine U-boats before the coast of Spain.

After the engagement of the Kriegsmarine (including U-boats) had been decided, entire Naval Task Forces were detached to Spain until early 1939, led by an ar-mored cruiser or light cruiser as flagship and compo-sed of several bigger and smaller warships. Mission time in theatre was generally 4 to 5 weeks, it could last, however, in some cases overlapping to several months. Beginning with the 4th Task Force (November/ December 1939 led by the armored cruiser Admiral Scheer) U-boats were included. Initial planning for the addition of U-boats was resumed on 02 November 1936, carried out by the then Befehlshaber der Aufklärungskräfte (= Commander Reconnaissance Forces), Rear Admiral Hermann Boehme, who also acted as Task Force Commander German Naval Forces Spain on the scene between 25 August 1936 to 03rd of August 1937.

The clandestine deployment even of two U-boats to the Mediterranean off the coast still controlled by the Republicans was given the codename “Operation Ursula” and designated to be a “training mission”. It was special to this mission that its rules of engagement allowed the attack of Republican (also called “red”) Naval Forces as well as merchant vessels loaded inside territorial waters. The U-boats selected to execute this mission were the new Type VII A boats U 33 and U 34 of the U-Flotilla “Saltzwedel”, which had been commissioned only shortly before in July respectively September 1936. To cover up the mission, the U-boats were given code names also in R/T message traffic: U 33 became “Triton” and U 34 became “Poseidon”.

The Commanding Officers having just commissioned the U-boats, but which were still rather inexperienced, were relieved from their commands temporarily for the purpose of this mission: Oberleutnant zur See (= Lieutenant) Ottoheinrich Junker of U 33 by the Commanding Officer of U 7, Kapitänleutnant (= Lieutenant Commander) Kurt Freiwald, and Oberleutnant zur See Ernst Sobe of U 34 by Kapitänleutnant Harald Grosse.

U 33 and U 34 departed their homebase Wilhelmshaven during the night 20 to 21 November 1936, to pass the English Channel during the night 21 to 22 November 1936, to eventually sneak surfaced through the Strait of Gibraltar during the night 27 to 28 November 1936. The area of operations assigned were the sea area off Alicante for U 33 and the sea areas off Cartagena for U 34, which were reached by both U-boats on 30 November 1936.

On 01 December 1936 at 19.02 hrs U 34 launched a first torpedo against an unknown Republican destroyer, but missed.

On 05 December 1936 at 06.37 hrs U 34 fired another torpedo, this time against the Republican destroyer Almirante Antequera, but missed again. On 08 December 1936 at 17.30 hrs U 34 had another unsuccessful torpedo launch against an unknown Republican destroyer.

U 34 - Indienststellung 1936
U 34 – Commissioning 1936

During this time U 33 had no favorable attack situations against Republican Naval Forces, although it sighted a convoy on 02 December 1936, but was harassed and kept away by an escort destroyer, and on 05 December it refrained from attacking a destroyer due to insufficient identification during the night. On 08 December 1936 it even had to let pass uneventful the clearly identified Republican cruiser Méndez Núñez.

On 09 December 1936, after 12 days of patrolling in the assigned area of operation the return of both U-boats was decided officially due to their fuel state. However, an important reason to do so was certainly the poor results achieved so far during the operation, which was about to cause some embarrassment for the young U-boat force still in the buildup.

On 10 December 1936, Generalfeldmarschall (= Field Marshal) Werner von Blomberg, the then War Minister of the Reich and Commander-in-Chief of the Wehrmacht, gave officially order to abandon “Operation Ursula”. On 12 December 1936, a successful attack was executed after all, when U 34 spotted through its periscope at about 14.00 hrs a Republican submarine off Malaga, to launch eventually a torpedo against it at 14.19 hrs. The 1,100 t submarine C-3 under the command of Alférez de Navio (= Sublieutenant) Antonio Arbona Pastor was hit and sank, just 3 sailors of the 36 strong crew (other sources even talk of a crew of 40 or 44, but the 3 survivors are reported correspondingly).

On 13 December 1936 during their homebound voyage U 33 and U 34 passed the Strait of Gibraltar and later the English Channel. Some sources say both U-boats to have arrived at Wilhelmshaven on 21 December 1936, others speak of the 24 December. Herzog even claims that the actual track of the return leg was ca-mouflaged by fictitious position reports, and that both U-boats were ordered to initially call at the port of Bruns-büttel at the river Elbe before returning to Wilhelmshaven, to be welcomed by the then Führer der U-Boote/ F.d.U. (= Flag Officer Submarines), Captain Karl Dönitz. Back at Wilhelmshaven, both U-boats were taken over again by their original Commanding Officers.

Beginning in the Summer of 1936 there were repeatedly so called “Non Intervention Agreements” to be managed by a “Non Intervention Committee”, which interdicted any direct intervention by means of arms deliveries or de-ployments of armed forces. As a matter of fact, however, these agreements were violated several times or were even revoked, the German Reich was no exemption from that. Noteworthy, the deployment of U 33 and U 34 occurred at a time when an agreement was negotiated to end certain submarine activities associated with the Spanish Civil War, eventually being signed as “London Submarine Agreement” on 28 November 1936, with the German Reich being a signatory state as well. The deployment of U 33 and U 34 was never halted, which consequently constituted a clear violation of the agreement just signed. In February 1937, a “Non Intervention Conference” at London resulted in not only another ban of further deployments of volunteers and war material to both sides of the Spanish Civil War, but also in the introduction of an international regime of sea control before the coasts of Spain. On 20 April 1937 the sea control regime went into effect officially assigning designated sea areas to Naval Forces of the signatories, according to that the Italian Navy and Kriegsmarine were to patrol the Mediterranean Coast of Spain (the German Navy mainly the sea area between Almeria and Valencia), which was controlled by the “Republicans”.

p283_1_05 p283_1_04

Kapitänleutnant (Lieutenant-Commander) Harald Grosse (left picture), CO of U 8, U 34, U 22 and U 58 -KIA on 23/02/1940

At the same time the German Navy continued to also operate in Atlantic sea areas before Spain. Following the air attack on the armored cruiser “Deutschland” on 29 May 1937 at the anchorage off the Island of Ibiza the German Reich gave notice of the termination of its membership in the “Non Intervention” agreement, withdrawing all German Naval unit from the international sea control regime. After that, the Kriegsmarine planned the missions of its task forces independently from other Naval Forces, but on 18 September 1937 a coordination agreement was signed with Italy.

Kapitän zur See Kurt Freiwald  Kommandant von U 7 und U 21, zugl. Kdt. auf U 33
Kapitän zur See (Captain) Kurt Freiwald
CO of U 7 and U 21, at the same time Co of U 33

Therefore, the deployments of German U-boats to the sea areas before Spain were executed in the Mediterranean as well as the Atlantic Ocean. However, in compliance with the coordination agreement with Italy, Ger-man U-boat patrols after the Autumn of 1937 were concentrated mainly in the Atlantic Ocean west off Gibraltar and in the Bay of Biscay. Other than the secret sending of U 33 and U 34 to the Mediterranean the further deployment of U-boats were reported about occasionally in the German media, mainly because they were somewhat “official” and also because foreign media sometimes reported about port calls of U-boats in Spanish habours.

After he has inquired from Rear Admiral Eberhard Godt (became later the Chief of Staff Operations at the Staff of the B.d.U. = Commander-in-Chief Submarines), who happened to be Commanding Officer of U 25 which was deployed to Spain as well, Herzog mentions a number of 12 further U-boats after U 33 and U 34 sent to the sea areas before Spain. In mid 1990, the U-boat Archive at Altenbruch carried out once, based on the documents and literature available then, a compilation of U-boat deployments from 1937 to 1939 to the patrol areas assigned in the Mediterranean and the Atlantic Ocean, which were ordered after the mission of U 33 and U 34. In January 1937 U 28 and U 35 are mentioned, both patrolling before Spain for a short period of time during their training voyage to the Azores (Port call at Ponta Delgada 22nd to 27 January 1937). In 1937 several deployments followed: In April/ May U 25and U 27, in May/ June U 28 and U 36, in June/ July U 33, U 34 and U 35, in July/ August U 14, U 19, U 25, U 26 and U 36, from the end of August to the end of October U 28, U 30 and U 31, from then end of October to mid December U 29 and U 34, but also U 25 (unconfirmed). In 1938 further deployments are known: In January U 36, in February U 32 and U 35, in September/ October U 27, U 30 and U 33 as part of the German Task Force led by the armored cruiser Deutschland, and in November U 27 and U 30 as part of the German Task Force led by the armored cruiser Admiral Graf Spee. The allegedly last U-boat was U 35, which left the port of El Ferrol at the Northwestern corner of Spain on 05 January 1939 homebound.

It becomes obvious that U-boats from both flotillas having been established in those years were deployed to Spain, i.e. not only from the U-boat Flotilla “Weddigen” at Kiel, but also from the U-boat Flotilla “Weddigen” at Wilhelmshaven. Also, not only the newest Type VII A U-boats (U 27 to U 36) were sent, but also the older U-boats of the Type II B (U 14 and U 19) and Type I A (U 25 and U 26). 6 U-boats were deployed three times (U 25, U 27, U 28, U 33, U 34 and U 35). During its second patrol in June 1937 U 33 was commanded again by the temporary Commanding Officer Kurt Freiwald, whereas the second patrol of U 34 was headed by the original Commanding Officer Ernst Sobe.

U 33 – commissioning in 1936

Many of the Commanding Officers who became famous during the war at sea in WW II were able to gain a weal experience from their deployments to the Spanish Civil War: In 1936 Gerhard Schreiber was First Watch Officer of U 34, in 1937 Victor Oehrn was Commanding Officer of U 14 and Fritz Frauenheim was First Watch Officer on board U 25, Werner Hartmann was Commanding Officer of U 26, his First Watch Officer was Günter Prien, Wolfgang Lüth was Second Watch Officer on board U 27 and Otto Kretschmer was Commanding Officer of U 35. After the end of the Spanish Civil War the Commanding Officers of the first two U-boats sent to Spain were given military decorations: Kurt Freiwald was awarded the Spanish Cross in gold, whereas Harald Grosse recei-ved the Spanish Cross in bronze, together with 4 more Commanding Officers.


The story of “Kriegsmarine U-boats in the Spanish Civil War” was told to the public rather filtered and much was simply concealed, in particular the deployment of the first two U-boats U 33 and U 34. However, some docu-ments have survived, e.g. a 55page final report from 14 December 1936 by Rear Admiral Boehme about the employment of U-boats in the Spanish Civil War, i.e. right after “Operation Ursula”. Also, some eyewitnesses have eventually told about their experiences, some of them still rather disguising (allegedly, the then F.d.U.= Flag Officer Submarines Karl Dönitz claimed still in early 1962 vis-à-vis Herzog that none of the U-boats sent to Spain had sunk a ship), others were more helpful (e.g. Schreiber and Godt). Therefore, a rather true picture of the deployment of the U-boats involved can be put together, although some uncertainties will remain due to the quality of the literature and sources available. Generally, the myths about the deployments seem to have been defeated. The young U-boat force of the Kriegsmarine made use of the framework set by the politics of the German Reich in support of Franco, to plan missions beyond mere training. At the end of 1938 some 45 U-boats had been commissioned. If one takes the statements by Eberhard Godt for granted and if one studies the files still available at the Federal Archive/ Military Archive, some 14 U-boats were sent to Spain, which makes a good quarter of the total number of U-boats commissioned at the time. So, valuable experiences could be gained, even “hot” torpedo launches against Republican warships. Whereas the deployments of U-boats to Spain after February 1937 can be justified by the international embargo agreements by and large, the secret and “hot” mission of U 33 and U 34 at the end of 1936 could be seriously questioned whether it really was in full observance of the rules of international law.


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Text: Peter Monte – Picture: Deutsches U-Boot-Museum