from five to seven months and included course instruction on reconnaissance, swimming, hand-to-hand combat, demolitions, marksmanship in both German and Allied weapons, conventional infantry tactics, and other specialized training. Brandenburg units were deployed as small commando outfits to penetrate into enemy territory and conduct both sabotage and anti-sabotage operations. Despite their demonstrated successes while incurring minimum casualties, many traditionally-minded German officers still found their use abhorrent. Most of the personnel were fluent in other languages, which allowed them, for example, to penetrate the Netherlands in 1940 disguised as Dutch barge crews just before the start of the invasion. In 1941, they preceded the invasion of Yugoslavia undercover as Serbian workers. During the night before Operation Barbarossa began, Brandenburger units crossed the Soviet border disguised as Soviet workers and Red Army soldiers. Others even adorned themselves in Arab garments to conduct surveillance on Allied warships traversing between the Straits of Gibraltar and North Africa ahead of the Wehrmacht deployment there. Correspondingly, Department II of the Abwehr, under which the Brandenburgers were subsumed, had a distinct sub-component for army, navy, and air force operations. Many of the Brandenburgers were misfits who could hardly be characterized as conventional soldiers, due in large part to the nature of their operations. They would mingle with enemy soldiers, secretly countermand orders, redirect military convoys, and disrupt communications—all the while collecting intelligence along the way. Ahead of the primary invasion forces in the USSR, operatives from the Brandenburg Division seized bridges and strategically important installations in clandestine missions lasting for weeks before they linked up with advancing forces. The predecessor formation to the Brandenburg Division was the Freikorps Ebbinghaus, which originated before the invasion of Poland in 1939. Colonel Erwin von Lahousen (and the defense groups of military districts VIII and XVII) from within Department II of the Abwehr, put together small K-Trupps (fighting squads), which consisted of Polish-speaking Silesians and ethnic Germans, whose job it was to occupy key positions and hold them until the arrival of regular Wehrmacht units. The first members of the "K-Trupps" were German nationals. Generally, these men were civilians who had never served in the army but were briefly trained by the "Abwehr" and were led by army officers. After the Polish campaign, this changed as these commandos became members of the Wehrmacht. Despite their seeming lack of prior experience, the demands placed on these newly formed commandos were high. It