In April 1941, the German Army invaded Yugoslavia and then Greece. Klingenberg, a company commander in the Das Reich division, led his unit to the capital, Belgrade, where a small group in the vanguard accepted the surrender of the city on 13 April. A few days later, Yugoslavia surrendered.[1][2]
Capture of Belgrade
In April 1941, Klingenberg was with SS troops taking part in the invasion of Yugoslavia. Klingenberg disobeyed orders, and decided to reconnoiter Belgrade, with his units far ahead of the main German army. Finding a boat, he crossed the river, with the intention of ferrying a sizable force across; however, the boat sank, and he was left with just six men. Klingenberg then encountered some Yugoslav troops who had captured a drunken German tourist, and captured them.
On the 11th April, after a number of firefights the six Germans, having sustained no casualties but capturing a number of Yugoslav soldiers, made it to the centre of Belgrade with the tourist and their prisoners. There they raised a German flag. Jevrem Tomić, the Mayor of Belgrade, came out to meet them, after Klingenberg bluffed, telling him there was an incoming artillery barrage and an impending Luftwaffe attack. Tomić and some garrison troops surrendered the city to them on 12 April.
At this point a few more of Klingenberg's men arrived the same way he had, and made a show of their presence, pretending that there was more of them than there were.[3][4][5] The German army eventually arrived, dumbfounded at the situation, having made a complex plan to take the city that was no longer needed, and was expected to cost thousands of lives.[1][2][6] A few days later Yugoslavia surrendered.[1][2] Klingenberg was awarded the Knight’s Cross for capturing the city, in effect capturing Belgrade with just himself, his six soldiers and the tourist.
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