By late 1942, the Germans had invaded deep into the Russian interior, their objective the vast oilfields of the Caucasus. The last obstacle that remained in their way was the city of Stalingrad. But far from being the final step in the conquest of the USSR, Stalingrad proved a bloodbath. After a terrible battle lasting “200 days”, it became the first major defeat for Hitler during WWII. Half-a-million Germans died there. Perhaps three times as many Russians lost their lives. The German Army was modern, well-trained and well-led, with state of the art military equipment, high morale and a string of victories behind it. By comparison the Red Army was inexperienced, old-fashioned, and ill-equipped. So how did the Russians win? Legend goes that it was “General Winter” who defeated the German Army–but forensic analysis and historical research show that coping with freezing weather was not the only ace in the Russians’ pack.