Good evening! Thanks for your input, E!
The naval warfare in the Bay of Biscay
After the failed coup d´etat, the rebel forces against the leftist Spanish Republic only had been successful in Navarre, Galicia, Spanish Morocco, the northen part of Castille, and a beach head in Andalusia (Seville, Cadiz and Algeciras), with some emblematic isolated pockets like the Alcazar of Toledo too. The main cities (Madrid, Barcelona, Valencia, Bilbao) and industrial centers (Barcelona, Bilbao) and mines (Asturies) remained loyal to the Republic, as it was the bulk of the Spanish Navy (but not the officer corps, so there was an accute deficit of officers and flag officers), and as the most resolutive and professional corps of the Spanish Army, the Army of Africa remained bottled in Morocco, for August 1936 there was a stalemate, with little rectifications to the front lines.
As the main base of the Spanish Navy, Ferrol, a well defended harbour with drydocks, shipyards and complete workshops, was in rebel hands, they assembled a fleet with the vessels available there: a battleship ready to being paid off, a 6 inch cruiser equivalent to the RN E class, and a 4 funneled destroyer and begun to harass the republican navigation in the Bay of Biscay harbours. In September, General Mola´s army set up an offensive and took Irun, Pasajes and San Sebastian, closing the french border to the republican territories at the north.
These facts forced to the republican government to made, in words of Alpert "the worst strategic decision of the SCW": Moving almost all the fleet from the Gibraltar Strait to the Bay of Biscay. At the cost of regaining briefly the superiority (but not the iniciative) at the North, within 10 days all the Army of Africa was in the peninsula, and few weeks later, almost all southern Andalusia, the Portuguese border and part Extremadura was secured, connecting General Franco´s army with the rest of the rebel forces at the castillian plateau (and putting the foundations for his future political gains, as the only victorious and decisive rebel general).
Let´s see what happened in the Basque Country. The government of the basque provinces was in hands of the PNV (Basque Nationalist Party) which was (and is) a liberal party, deeply catholic and very moderate, the only point of coincidence with the mostly socialist (the non-democratic socialism of the first half of the XX century), mostly atheist and revolutionary Frente Popular was the promise of autonomy: an odd mating between two very different ideologies. After the autonomy was attained, the basque government created the Basque Auxiliary Navy, centered in PYSBE big cod trawlers
which were ocean going trawlers able to deal with the heavy seas of the Great Banks and called there "armed bous". Depicted here is Nabarra (ex-Vendaval) an Aberdeen built steamer, armed with one, then with a second 4 inch guns of british conception. Complemeted with two Schwarzlose 8 mm AA MG in the bridge wing. The bous were manned by PYSBE sailors and merchant officers with naval homologation and little combat experience. The only military personnel was the guns crews. As bowsprit jack, the basque nationalist flag was flown.
Unfortunatelly for the Spanish Republic, in October the new 8 inch nationalist cruiser Canarias and the 6 inch Cervera departed to the south and after sinking a republican destroyer, regained the control of the Straits. This movement, obliged a forced return of the Republican fleet to Cartagena, lefting in Bilbao only a destroyer and a couple of submarines. But having the naval bases of Cadiz and Ferrol and also the friendly lenience of the portuguese government, for the Nationalist ships was relatively easy shift north to south and vice-versa.
Isolated in the north, the Basque government relied only in shipborne trade: exporting minerals and importing food and weapons. The basque bous were much more active than the republican destoyer Jose Diaz left at the north. This is context the battle of Cape Machichaco was fought.
The nationalist naval intelligence was instructed that the big and fast republican diesel motor vessel Mar Cantabrico (1)
with an important load of armament from Mexico and the United States, was in route to the Bay of Biscay republican harbours. So late in February almost all the rebel fleet was sent to screen the sea from the French border up to Galicia: cruiser Canarias off Bilbao, battleship España off Santander, auxiliary cruiser Ciudad de Valencia off Gijon, nationalist bou Galerna from the mouth of the Loire to the border, destroyer Velasco and other bous making a barrier off Pasajes, and the auxiliar cruiser Ciudad de Palma as far as the French island of Ouessant.
In parallel, the Basque government instructed to the 4 bous available to give escort to the basque requisitioned steamer Galdames with general cargo and several tons of coins (1 and 2 pesetas coined in Belgium), from Baiona to Bilbao. In March 4th 1937, Canarias recibed the order to capture Galdames.
During the night, the basque formation was dispersed by the bad sea, lack of visibility and compulsory radio silence, so Galdames was escorted only by Nabarra and Donostia. Off Bilbao, Bizkaya and Gipuzkoa were trying to find the missing vessels. Few hours before, Canarias captured the estonian vessel Yorkbrook loaded with 400 tons of armament and was instructed to proceed to Pasajes, a basque harbour in nationalist hands. Early in the morning, Canarias found Gipuzkoa some miles East from the mouth of Bilbao's stuary and the bou was shelled and nearly disabled, but managed to reach Portugalete.
Then, Canarias tried to find and capture Galdames, going to the north. After identifing the merchant vessel, Canarias opened fire and attained a 4.7 inch hit at Galdames which surrendered. Nabarra tried a gallant defense of the merchant exchanging fire with the cruiser for nearly an hour. Finally, a shell struck at the bou´s boiler room with heavy loss of life and a quick loss of speed. Only 20 wounded and burned survivors managed to escape, being captured by Canarias. Nabarra blew up and sunk off Cape Machichaco.
Donostia (a british built trawler of the Castle Class) never was in range to use its 3 inch artillery and managed to reach a French harbour.
Several miles far from the battle, Bizkaya found and recapture Yorkbrook, entering to Bermeo. 3 days latter, Canarias found Mar Cantabrico and captured her, the merchant was converted in an auxiliar cruiser with 4 x 6 inch guns (qv).
The sister ship of Vendaval / Nabarra was Galerna. Initially used by the basque government as a transport between french and basque harbours until captured by a trio of nationalist bous late in 1936. Modified at Ferrol, it was an useful vessel in francoist northen fleet, with tasks from the rutinary blockade of the republican harbors, to shelling shore batteries, fighting against a destroyer and capturing several transports and an oil tanker.
Credits: Colombamike's aid was invaluable: from the blueprints, to the precise indications to correct several mistakes in my drawings; and from the battle´s map, to the log book of Canarias of that week
. Lots of thanks for your help... and your patience!
(1) The excellent Novice´s drawing is flying a royal red and yellow flag instead the republican tricolor flag.