Generalfeldmarschall Paul Hausser- Commander of German forces in the Balkans
Immediately following their declaration of war on February 26, German forces under the command of Generalfeldmarschall Paul Hausser launched attacks against the cities of Vraca and Sofia. Tsar Boris III, in personal command of Bulgarian forces in Sofia, perhaps equally realizing that he could not hold the German onslaught and trying to avoid damage to his beloved capital, quickly ordered his forces to retreat and gave the city over to the invading army. As he pulled back, he sent similar orders to General Lukash who was in command of Bulgarian forces in Vraca.
In only a few days, the German army had captured the Bulgarian capital and put the bulk of the Tsar's army into full retreat. The early smashing successes in Sofia and Vraca were, however, to be the last easy German advances of the campaign. Boris had retreated to defensive positions in Bulgaria's mountainous interior and initial German attempts to drive him out of his mountain strongholds were repulsed with serious losses. After the defeats, his first since the 1st Battle of Warsaw nearly seven months previous, Hausser quickly realized that the campaign was likely to be much longer than he had first anticipated. Seeing that his panzer forces would be useless in the mountains, he sent them south to capture the province of Gorna Dzhumaya and open up the Greek frontier. As for the Bulgarian front, Hausser resigned himself to a long drawn-out battle against Boris' forces.
German mountain gun in position near Yumrukchal
As Hausser and his men settled in for the coming campaign, they were joined by a rather unique formation. On February 23, Germany had decided to grant independence to the state of Croatia, which would naturally be controlled by a fascist and pro-German government. It was a calculated move designed to ease the burden of garrisoning the conquered areas of the former Kingdom of Yugoslavia. Upon granting the independence of the new nation, the Germans suddenly found themselves inundated with thousands of young Croatians who wished to volunteer for the German war effort. In this, Reichsfuhrer-SS Himmler saw an opportunity. Himmler had been arguing for the recruitment of foreign volunteers into his Waffen-SS for some time. He imagined men from all corners of Europe joining together under the banner of the SS to fight in a great crusade against the enemies of Germany and of the Aryan race. The Croatian volunteers would make up his first such SS "foreign legion". Three full divisions were created and grouped into the I. Kroatisch Korps der SS. After it's formation, the unit was deployed to Bulgaria to receive it's baptism of fire.
Members of the I. Kroatisch Korps der SS
On the other side of Europe, an equally heated battle was underway. This battle however, was being fought far above the ground. After replacing the tremendous losses incurred during the invasions of France and Belgium, the Luftwaffe had risen again to challenge the RAF for control of the skies. After the fall of France, tentative plans had been drawn up for an invasion of the British Isles codenamed Unternehmen Seelöwe. Crucial to the success of this plan was the complete defeat of the RAF. At a gathering of his top military advisers, Hitler had put to them the question of whether the Luftwaffe could wrest control of the skies above southern England and the English Channel from the RAF. While most of the senior military men present were doubtful of the Luftwaffe's ability to destroy the RAF, Reichsmarschall Hermann Goering had immediately assured the Fuhrer that his men could accomplish the task.
Reichsmarschall Hermann Goering
In the end, Hitler went with the majority and had decided on the more moderate course of defending the skies of Germany and occupied Europe from the relentless Allied bombing campaign that had been running non-stop since October, and to shelve Unternehmen Seelöwe for the time being. To this end, the full might of the Luftwaffe's interceptor arm had been stationed along the coast of France, Belgium, and the Netherlands in the beginning of February. Allied bombing formations quickly found themselves being intercepted over the English channel by swarms of German aircraft. By the beginning of March, the number of bombing runs being made by the Allies had dropped off sharply and the number that actually reached their targets was fewer still. The Germans were winning the air war.
Messerschmitt Bf109-E interceptors in northern France