As the Germans advanced towards Russia during Operation Barbarossa in the second half of 1941, they came across a line of outdated Soviet defensive fortifications known as the Stalin Line. Following the construction of the Molotov line further west after the beginning of the war, the fortifications of the Stalin Line had been largely disarmed of their main defensive weaponry and thus were greatly weakened during the attempt to block the German approach towards Smolensk and Moscow. On 30 July 1941, General Georgy Zhukov was placed in charge of the Reserve Front and immediately tasked with the construction of new defensive line to protect Moscow. Many tens of thousands of civilians and soldiers were drafted to build the makeshift defensive fortifications, which became known as the Mozhaisk Defensive Line. As the Germans edged further east, passing the Stalin line and engaging in bitter fighting for Smolensk, the Mozhaisk Defensive Line became Moscow’s primary means of defence.
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