Generaloberst Gerd von Rundstedt- Oberbefehlshaber West
When German troops crossed the border into Spain on the morning of July 22, they did so under the command of Generaloberst Gerd von Rundstedt. Rundstedt was a man who, in the summer of 1940, felt deeply under appreciated both by the Fuhrer and by the rest of the Wehrmacht's hierarchy. Despite having planned and executed the winter campaign that had seen Belgium and France fall to German arms in little more than a months time, he had received little recognition for his efforts other than being officially named Oberbefehlshaber West- a position that he had already held in fact if not in name. Meanwhile, two of his subordinates - Paul Hausser and Ewald von Kleist- had seen their stars rise dramatically and had been promoted to the rank of Generalfeldmarschall. Hausser and Kleist had then gone on to frontline commands while he himself was left to guard the French coast. Rundstedt saw the invasion of Spain as his chance to gain the recognition that he felt he deserved and he was resolved to utterly crush the Spanish Army and end the conflict as swiftly as possible.
His plan called for a strike into the Spanish province of Biscay and the occupation of the city of Bilbao. From there, his force- dubbed Heeresgruppe Spanien- would branch off and divide into three separate Armeegruppen and continue along three lines of advance. Armeegruppe A would move west until it reached the Reich Protectorate of Galicia, and would then move south through the Castilla y León region until it bypassed the city of Madrid, at which point it would swing east. Armeegruppe B would advance from Bilbao south toward Madrid and, together with Armeegruppe A, would encircle and capture the city. Rundstedt hoped that this move would also lead to the encirclement and destruction of most of the Spanish Army. While those two Armeegruppen advanced on the Spanish capital, Armeegruppe C was to move east following the occupation of Bilbao and cut off and occupy the Catalunya region. Once these operations were completed, and if Spain had not surrendered, the three army groups would then move south and destroy whatever Spanish Army formations remained until they reached the ultimate goal of the operation: Gibraltar.
Of all of the steps of Rundstedt's invasion plan, the most daunting was actually the first one. Heeresgruppe Spanien would be invading into the mountainous Basque region along a rather narrow front. The terrain was extremely inhospitable to panzers, meaning that German infantry would have to shoulder the burden of the attack alone. Once the Basque region fell, however, Rundstedt would unleash his panzers and it was expected that the remainder of the campaign would be conducted with relative ease.
Heinkel He-111s in the skies above Spain on the morning of July 22, 1940
The fighting opened with a massive aerial bombardment in the early hours of July 22. Six Luftflotten of Heinkel He-111 tactical bombers and Stuka dive bombers totaling over 3300 aircraft hammered positions throughout northern Spain in the most awesome show of aerial power yet shown by Germany during the war. German infantry swarmed into Spain in their wake and the Spanish border positions collapsed with shocking speed. By the end of the day, German troops had reached Bilbao and all Spanish formations in the area were in full retreat.
With the fall of Bilbao and the capture of Biscay Province, the entire German invasion force of over 200,000 infantry and nine full panzer divisions was able to pour into northern Spain and launch themselves into the next phase of the attack.
As the invasion unfolded in Spain, a group of volunteer soldiers were completing a special kind of training back in Germany. Three full divisions as well as an elite SS regiment had been formed into something not yet seen in the history of Germany's armed forces, and these men were to figure prominently in the next stages of the war.