At the end of December 1937, Red Army and EDC offensive against Nazi Germany and his allies began. To 12th January 1938, Soviet armies liberated Konigsberg, half of Hungary, Wien, southern Germany and large parts of Italy. Red Army Central Commanding with Czechoslovakian and Polish officers started to prepare strategic attack offensive against German defense lines in east Germany. Hitler Defense Line became strongest point of German defense with more then 70 infantry and 20 tank divisions with support of 2500 artillery batteries and all Nazi air forces in Germany. Red Army commanders decided to start main part of offensive against Dresden with Czechoslovakian support. At 15th January, Andrei Navrchov took command over whole front and offensive. With commanders Zhukov, Tukhachevsky and Roko