Operation Stonewall

Operation Stonewall was a World War II operation to intercept blockade runners off the west coast of 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 by Germany of seaborne goods. Although rich in many basic industrial materials, Germany, like Britain, could not produce some essentials. These included rubber, tin and tungsten.

Until the German invasion of the Soviet Union in June 1941 (Operation Barbarossa), the blockade was evaded via the Trans-Siberian Railway and large quantities of materials were shipped by this route. Once this was closed, German and Italian ships, stranded in Japan and Occupied Singapore, were used to bring in these essentials to ports in Occupied France. These were the blockade-runners.

Although an organised interdiction against these blockade-runners could not be set up until December 1943, several ships were intercepted and sunk in the Atlantic and Indian Oceans. Few actually managed successful runs.

The New Zealand cruiser, HMNZS Gambia, joined the operation in December, 1943, and operated from Horta, in the Azores, with HMS Glasgow, patrolling an area north of the islands.

On 23 December, aircraft from the American escort carrier USS Card spotted a suspected runner and there were further reports of a flotilla of destroyers escorting another merchantman west from France. HMS Gambia, Glasgow, and HMS Enterprise formed a cordon to intercept. Aircraft attacked the flotilla, now escorting an incoming merchantman (SS Osorno), reporting a hit and a near-miss on Osorno.

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