Hitler's assault of Russia in 1941 transformed a European difference into a worldwide conflict and brought two political ideologies and two influential dictators into an immense fight. However, the campaigns of the summer 1942 and later of summer 1943 swung the unsteadily poised equilibrium of battle positively against Germany. The Russian defense of Stalingrad has been recorded in the archives of history as one of the classic examples of fortress defense. The defenders not only dissatisfied the frequent and desperate attempts by the Germans to get hold of Stalingrad but also succeeded in causing such great attrition on the adversary that it eventually resulted in the surrender of the Germans Sixth Army.