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WWII On This Day: December 13

What happened on December 13 during World War II? This date brings together 3 events from 1940, 1943 and 1944, with period photographs and links to the full operations documented across WW2 Theatres.

1940
A reconnaissance detachment of the German 5th Panzer Division entering Athens on 27 April 1941.
Bundesarchiv Bild 146-1979-123-32 · CC BY-SA 3.0 DE · Source
German Invasion of Greece, April 1941

Hitler orders preparations for Operation Marita

Directive No. 20, issued on 13 December, ordered the German armed forces to prepare Operation Marita. The plan envisaged a force assembling in southern Romania, moving through Bulgaria and occupying the northern Aegean coast, with the option of extending the operation across mainland Greece. German strategy linked the Balkans to wider concerns: British air and ground forces in Greece threatened the Romanian oil region and Axis control of the eastern Mediterranean approaches. The directive preceded the later British expedition and therefore formed part of a German strategic calculation already under…

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1943
Kalavryta after German forces burned the town during the December 1943 operation.
Kalavryta after German forces burned the town during the December 1943 operation. State Archives of the Republic of North Macedonia · Public domain Source
Reprisal and Massacre

German forces kill the men of Kalavryta and burn the town

German troops reached Kalavryta during a large anti-partisan operation in the Peloponnese. The male population was separated and taken outside the town, while women and children were confined in the school. The men and boys selected for execution were shot and Kalavryta was burned. The massacre formed part of a wider operation across the surrounding villages and monasteries, where collective punishment followed the killing of German prisoners by resistance forces. The destruction of the town left women, children and surviving families in a burned settlement after the executions. The combination…

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1944
Infantrymen of the U.S. 4th Infantry Division rest on a slope in the Hürtgen Forest on 18 November 1944.
U.S. Army Signal Corps / National Archives · 18 November 1944 · Public domain · Source
Aachen and the Hürtgen Forest

The first ground attack aimed at the dams

The 78th Infantry Division opened the first ground attack whose operational purpose included the Roer dams. The advance moved through the Monschau corridor while other units fought around Kesternich and the approaches to the reservoirs. The division gained its initial objectives and remained short of the reservoirs. Fighting at Kesternich hardened as German formations were also being repositioned for the Ardennes offensive.

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