Sea defence zone

A sea defense zone (Seeverteidigung) was a tactical area in the organization of the Kriegsmarine intended to provide operational command of all German naval forces, within a given geographical area, in the event of actual enemy attack on the coastline of occupied Europe.

The first sea defense zones were established in the spring of 1940 to protect the large amount of coast line which Germany had acquired after invading the Low Countries, Denmark, Norway, and France. Originally, commanders of the sea defense zones were known as "coastal commanders" (Küstenbefehlshaber). In the summer of 1940, in preparation for Operation Sea Lion, the Kriegsmarine established seven "sea command sectors" (Seebefehlsstellen) which were commanded by officers ranked Kapitän zur See. All of the sea command sectors had been disestablished by the end of 1941.

Original Sea Command Sectors (1940)

In the spring 1940, the Kriegsmarine began to reorganize coastal defense under a new position known as Kommandant der Seeverteidigung (Sea Defense Zone Commander). Between 1941 and 1945, the sea defense zones were expanded and retracted, gaining and losing territory to other zones or to the advance of allied or Red Army (Soviet) forces. Logistically, the sea defense zones were strictly a Navy command, but were integrated into the Atlantic Wall which was generally overseen by the German Army.

Sea defense zones were normally commanded by an officer ranked as either Kapitän zur See or Konteradmiral. The sea defense zone commander answered to a Navy regional commander and would take tactical control over all shore forces in a given area should an enemy launch an attack against a segment of German coastline.

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