It consisted of the 136th, 138th and 139th Mountain Replacement Regiments and the 112th Artillery Replacement Regiment, plus supporting units. It began the war on border guard duty in the mountainous region between Austria and Yugoslavia with the primary mission of training reservists and replacements for the regular mountain divisions. In the spring of 1941 it joined the invasion of Yugoslavia, with the three mountain regiments given responsibility of seizing control of Carniola and Carinthia on the Yugoslav side of the border, which they carried out quickly and effectively against little to no resistance.[1]