Arko = "Artillerie Kommandeur"
An "Arko" was a semi-independent HQ unit under which artillery elements could be assembled and centrally controlled. Such a formation was extremely flexible: any type of available artillery in any desired numbers could be placed under the control of an Arko. The Arko itself would either be temporarily attached to any formation from a division to an Army, depending upon the task at hand, or could operate semi-permanently as an ad hoc artillery division. They would be committed anywhere their support was required and could quicklbe dissolved and re-organized if circumstances demanded it.
The following passage from "Inside the Afrika Korps – The Crusader Battles, 1941-1942" by Colonel Rainer Kriebel; edited by Bruce Gudmundsson should explain the function of the "Arko" –
THE ARRIVAL OF GERMAN ARTILLERY
In addition to the division artillery and Italian army artillery already on the spot, it was regarded as essential to have at least six more German heavy army artillery battalions. Of these, the following elements had arrived at the beginning of October:
> Headquarters of Artillery Command 104 (ArKo 104)
> 1 battalion of 10cm guns
> 12 battalion of 21cm howitzers (less one battery)
2 army coast artillery battalions of 15cm guns
Not yet arrived:
> 1 observation battery
> 1 army coast artillery battery
> 1 battery 17cm guns
> 1 battery 21cm howitzers
> 1 battalion French heavy field howitzers (15cm)
Note: A German artillery command (Arko) was a floating headquarters that could control the fire of a large number of artillery battalions. On the eve of World War II, the German Army intended to put an artillery command in every division, giving that division the ability to control the fire of artillery units greatly in excess of the three or four organic artillery battalions. The rapid expansion of the German Army during the war, however, made this plan unworkable: there were simply not enough artillery officers qualified for this sort of work. As a result, each artillery command tended to serve as sort of "flying circus" that moved from one part of the front to another. For details, see Bruce Gudmundsson, "On Artillery", WEstport CT, Praeger, 1993.
FWIW, Gudmundsson's "On Artillery" is a terrific reference work.
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