Operation Bernau

Operation Stonewall was a World War II operation to intercept blockade runners off the west coast of German-occupied France. It was an effective example of inter-service and international co-operation.

From the start of the war, the Allies had maintained a blockade against the import of seaborne goods to Germany. Although rich in many basic industrial materials, Germany, like Britain, could not produce some essentials. These included rubber, tin and tungsten.

Until Germany invaded the Soviet Union it evaded the blockade via the Trans-Siberian Railway. Large quantities of materials were shipped by this route. After this was closed, German and Italian ships, stranded in Japan and Japanese-occupied Singapore, were used as blockade runners to bring in these essential goodss to ports in occupied France.

Although organised interdiction against these blockade runners was not set up until December 1943, the Allies intercepted and sank several ships in the Atlantic and Indian Oceans. Few ships managed successful runs.

The Royal New Zealand Navy light cruiser HMNZS Gambia joined the operation in December 1943, operating from Horta in the Azores. The Royal Navy light cruiser HMS Glasgow patrolled an area north of the islands.

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