Gallwitz was one of the German generals involved in joint operations with the armies of the Monarchy. He was born in 1852 and was the commander of an independent cavalry corps at the outbreak of the Great War, and from September 1914 became commander of the German 8th Army on the Eastern Front. From 1915, as the commander of the 12th Army led the persecuting German troops after the Gorlice breakthrough. He was awarded the Pour le Mérite Order for his achievements at this time. He was with the troops of the Monarchy until March 1916, later as commander of the 11th German Army, taken over from General Mackensen. I wrote earlier about the badge of the 11th Army here: several Austro-Hungarian units were subordinated to it.
Several of the general portraits of the Arkanzas company were modeled on German generals who also commanded Austro-Hungarian troops. Such was Gallwitz’s badge.