The Legion was the most powerful and successful Muslim militia in the Tuzla region, and fought Yugoslav Partisans and Chetniks in northeastern Bosnia between December 1941 and October 1943.

By April 1942 it was effectively operating outside of the control of the Croatian Home Guard, although they continued to supply arms and ammunition to the Legion.

By the end of December 1941, the Legion had commenced forming battalions in Bijeljina, Brčko, Gračanica, Puračić, Živinice and Tojšići.

[2] By this time the NDH authorities in Tuzla were reporting that the Legion did not recognise Ustaše rule, and was effectively operating outside of Croatian Home Guard control.

As part of this push, the leaders petitioned Adolf Hitler in late 1942 for the creation of a "Bosnian Guard" based on the Hadžiefendić Legion, to be under the direct control of the German Wehrmacht.