In March 1942, Hitler issued his Directive 40, establishing the 'Atlantikwall'. This mammoth construction project stretched from the northernmost tip of Norway, to the south of France. This followed Hitlers October 1941 directive, which instructed the transport of massive amounts of labour and material to the Channel Islands, to convert them into an 'impregnable fortress'. Those returning in 1945 found their island disfigured with German concrete. They were greeted by towers of several stories, gun-casemates, emplacements, tunnels and bunkers. The situation was worse on Alderney, with the morbid discovery of a mass grave of 389 people on Longis Common. The Germans had employed the might of the Organisation Todt to construct the defenses, the same organization that had lead the construction of the Autobahn and the West Wall some years earlier. The organisation imported some 773 German workers, and 4265 foreign workers. The foreign workers were made up of conscripted and forced labour, many North Africans from the recently capitulated French territories of Morocco and Algeria. Some 1018 French North Africans were recorded on the island. The bulk of the O.T. was withdrawn in 1944, leaving several positions in a half finished state. 

The question is often raised- why? Why was so much manpower and material expended in the Channel Islands, while vast swathes of the Atlantic Coast were left comparatively undefended, especially considering this would be the undoing of the Germans in Normandy. This first reason is the most commonly cited, simply being that Hitler had captured an English territory, and wanted to hold onto it for its propaganda value, and this is true. The scenes of British policemen opening doors for German officers, locals fraternizing with them, and of course the defenses themselves, were powerful tools of propaganda. The second however, is more pragmatic, and at least explains why such a concentration of powerful and modern artillery was planned for the islands, this being that along with a 36cm battery on the island, there would be two more on the continent. Together, the batteries would be able to block the bay of St Malo, significantly decreasing the amount of defenses needed. Therefore, logic follows that many of the infantry coastal defenses were to protect the heavy artillery. In the event, the modern 15cm SK/C28 naval guns could not be sourced, and had to be supplemented by introducing much lighter army artillery positions, manned by the Heeres Küsten Artillerie Regiment 1265, mostly comprising Vf positions fieldworks supporting guns of significant vintage. In 1944, the 15cm K18 batteries of 13. & 14./ H.K.A.R. 1265, Scharnhorst and Gneisenau respectively, were transfered to Jersey to protect its east coast against the newly hostile continent only a stones throw away.

There was never a fight for the islands, although various raids were conducted throughout the duration of the occupation, no invasion came. It was that final year of the occupation that was certainly the most brutal, with no supply ships coming to the island of 24,000 until the S.S. Vega in December 1944.