Analysis of information sources in references of the Wikipedia article "泥濘道路季" in Chinese language version.
During the Mongol invasion of the Rus' principalities in 1238-1240, Novgorod escaped destruction by the Mongols due to an early spring, which transformed the routes to Novgorod into a muddy bog.
By the time the Germans approached their major objectives such as Rostov, Moscow, or Leningrad the campaigning season was over and Barbarossa was off his horse. [...] [Hitler] had not planned to fight in Russia during the fall and winter. He had stated in his Directive No. 21 that this was to be a 'lightning campaign' to be won in two to four months maximum. [...] the cause of failure was the proposition that the Soviet Union could and would be defeated in a blitzkrieg.
whilst it was almost impossible to drag the gun-carriages through the half-frozen mud(regarding November 20, 1812)
whilst it was almost impossible to drag the gun-carriages through the half-frozen mud(regarding November 20, 1812)
