During the
Spanish Civil War, the
Second Spanish Republic had allowed an autonomous government in those Basque areas of
Spain that had not been taken by the
Nationalist faction, like
Biscay and parts of
Gipuzkoa. The coast of
Galicia, along with the
Ferrol naval headquarters, became part of rebel-held territory early in the
Spanish Civil War. When the Republican Navy became mainly confined to the
Mediterranean Sea, after the failure of the
blockade of the
Gibraltar Strait, its operations in the Bay of Biscay were taken over by the Basque Auxiliary Navy. Basque Auxiliary Navy ships engaged mainly in
minesweeping operations. They also played a key role in the evacuation of civilians who fled as the rebel armies advanced from coastal cities such as
Gijón and
Santander. The first naval action against
Francoist forces took place on 15 November 1936, when the Nationalist destroyer attempted to intercept the armed trawlers
Gipuzkoa and
Bizcaia (still under their peacetime names of
Mistral and
Euzkal-Erría). The trawlers were steaming for
Biarritz,
France, to escort a freighter when they were spotted by the warship 40 miles off
Pasaia. In the ensuing battle,
Velasco was hit and limped away, while
Gipuzkoa received some damage on her forecastle, with two seamen wounded.
Gipuzkoa finally arrived at Portugalete in flames and
Bizcaia headed for
Bermeo, where she met the
Estonian merchantman
Yorbrook, previously captured by the
Canarias, and forced her to make port.
Donostia sought shelter in France. ==Naval units of the Basque Auxiliary Navy==