XXXIX Reserve Corps (German Empire)

The XXXIX Reserve Corps (German: XXXIX. Reserve-Korps / XXXIX RK) was a corps level command of the German Army in World War I.

XXXIX Reserve Corps XXXIX. Reserve-Korps
Flag of the Staff of a Generalkommando (1871–1918)
Active	December 1914 - post November 1918
Country	German Empire
Type	Corps
Size	Approximately 26,000 (on formation)
Engagements	World War I
Insignia
Abbreviation	XXXIX RK

Formation

XXXIX Reserve Corps was formed in December 1914.^[1] It was part of the second wave of new Corps formed in the early stages of World War I consisting of XXXVIII - XXXXI^[2] Reserve Corps of 75th - 82nd Reserve Divisions (plus 8th Bavarian Reserve Division). The personnel was predominantly made up of kriegsfreiwillige (wartime volunteers) who did not wait to be called up.^[3] It was still in existence at the end of the war.^[4]

Structure on formation

On formation in December 1914, XXXIX Reserve Corps consisted of two divisions.^[5] but was weaker than an Active Corps

• the divisions were organised as triangular rather than square divisions with three infantry regiments rather than four, but had a brigade of two field artillery regiments
• Reserve Infantry Regiments consisted of three battalions but lacked a machine gun company^[6]
• Reserve Cavalry Detachments were much smaller than the Reserve Cavalry Regiments formed on mobilisation^[7]
• Reserve Field Artillery Regiments consisted of two abteilungen (1 gun and 1 howitzer) of three batteries each, but each battery had just 4 guns (rather than 6 of the Active and the Reserve Regiments formed on mobilisation)^[8]

In summary, XXXIX Reserve Corps mobilised with 18 infantry battalions, 2 cavalry detachments, 24 field artillery batteries (96 guns), 2 cyclist companies and 2 pioneer companies.

Corps	Division	Brigade	Units
XXXIX Reserve Corps	77th Reserve Division[9]	77th Reserve Infantry Brigade	255th Reserve Infantry Regiment
			256th Reserve Infantry Regiment
			257th Reserve Infantry Regiment
		77th Reserve Field Artillery Brigade	59th Reserve Field Artillery Regiment
			60th Reserve Field Artillery Regiment
			77th Reserve Cavalry Detachment
			77th Reserve Cyclist Company
			77th Reserve Pioneer Company
	78th Reserve Division[10]	78th Reserve Infantry Brigade	258th Reserve Infantry Regiment
			259th Reserve Infantry Regiment
			260th Reserve Infantry Regiment
		78th Reserve Field Artillery Brigade	61st Reserve Field Artillery Regiment
			62nd Reserve Field Artillery Regiment
			78th Reserve Cavalry Detachment
			78th Reserve Cyclist Company
			78th Reserve Pioneer Company

Combat chronicle

In 1915, the German offensive in Courland was intended to be a diversion while the main effort was made further south by the German 11th Army and Austro-Hungarian 4th Army in the Gorlice–Tarnów Offensive.

Armee-Abteilung Lauenstein (Army Detachment Lauenstein) was formed by upgrading XXXIX Reserve Corps of 10th Army^[11] on 22 April 1915.^[12] It was named for its commander, Generalleutnant Otto von Lauenstein, who retained simultaneous command of XXXIX Reserve Corps. It was directly under the command of OB East.^[13]

Due to its success, it was continuously reinforced until it was raised to the status of an army as the Army of the Niemen on 26 May 1915. Generalleutnant von Lauenstein remained as commander of XXXIX Reserve Corps.

Commanders

XXXIX Reserve Corps had the following commanders during its existence:^[14][15]

From	Rank	Name
24 December 1914	Generalleutnant	Otto von Lauenstein
7 July 1916	Generalleutnant	Hermann von Staabs[16]
3 December 1917	General der Infanterie
16 March 1918	Generalleutnant	Paul Grünert [de][17]
23 May 1918	General der Infanterie	Hermann von Staabs

Glossary

• Armee-Abteilung or Army Detachment in the sense of "something detached from an Army". It is not under the command of an Army so is in itself a small Army.^[18]
• Armee-Gruppe or Army Group in the sense of a group within an Army and under its command, generally formed as a temporary measure for a specific task.
• Heeresgruppe or Army Group in the sense of a number of armies under a single commander.

See also

• Germany portal

• Armee-Abteilung Lauenstein