The capitulation of the Wehrmacht’s Heeresgruppe B in the Ruhr heralded the disintegration of organised German resistance in the West. With the Allied armies at the zenith of their power, and the Red Army advancing on all fronts, the British wanted an all-out drive on Berlin to end the war and keep the Soviets as far to the east as possible. But Supreme Commander Allied Expeditionary Force Dwight D Eisenhower had other ideas.
Politically naive, he – along with his president – believed Stalin was an ally who could be trusted, and also thought the blood price to take Berlin would be too high. But above all he feared a Nazi bogeyman in the form of the Alpenfestung – the Alpine For tress, or National Redoubt. First mooted in late 1943, Allied intelligence had picked up on the idea of an impregnable stronghold in the mountains extending from Salzburg in the east to Lake Constance in the west. Garrisoned by thousands of Nazi fanatics, equipped with state of the art weapons manufactured in underground factories, the Alpine Fortress could extend the war almost indefinitely.
This apparently fantastical idea was bolstered when Supreme Headquarters Allied Expeditionary Forces (SHAEF) began to receive reports from February 1945 onwards that the Nazis were moving whole cadres of military staff and party officials south from Berlin to the area around Hitler’s retreat at Berchtesgaden in the Bavarian Alps. There, they were joined by V-2rocket scientists evacuated from the Peenemünde research facility and forced labourers sent to build for tifications.