The so-called ‘Axis allies’ like Romania, Hungary, the Slovak Republic, Croatia, and Bulgaria all contributed troops and materiel. The Romanians, for instance, contributed multiple field armies to the Nazi invasion of the Soviet Union. Rob Citino has remarked in one of his guest lectures that at some crucial points of the war (the onset of Operation Uranus for instance, the Soviet counterattack at Stalingrad) the military fortunes of the Wehrmacht more or less fell on the shoulders of the Romanian Army.