9. Armee 9th Army
Flag of the Staff of an Armee Oberkommando (1871–1918)
Active	19 September 1914 – 30 July 1916 6 September 1916 – 18 September 1918
Country	German Empire
Type	Army
Engagements	World War I Eastern Front Battle of the Vistula River Battle of Łódź (1914) Battle of Bolimów Romanian Campaign Battle of Transylvania Battle of Mărăşti Western Front Second Battle of the Marne
Insignia
Abbreviation	A.O.K. 9

The 9th Army (German: 9. Armee / Armeeoberkommando 9 / A.O.K. 9) was an army level command of the German Army in World War I. It was formed in September 1914 in Breslau to command troops on the southern sector of the Eastern Front. The army was dissolved on 30 July 1916, but reformed in Transylvania on 6 September 1916 for the Romanian Campaign. It was transferred to the Western Front on 19 June 1918 where it was finally dissolved on 18 September 1918.^[1]

History

First formation

The 9th Army Headquarters was established in Breslau on 19 September 1914 and commanded units drawn from the 8th Army, the Western Front and other units in Upper Silesia.^[2] It was originally placed on the southern sector of the Eastern Front on the left flank of the 1st Austro-Hungarian Army.

Second formation

9th Army was reformed for the Romanian Campaign in September 1916. Along with the 1st Austro-Hungarian Army (1st A-H Army) it formed the Siebenburg Sector and had the following units:^[5]

• XXXIX Reserve Corps
  • Group von Szivo (A-H)
    • Group Danube (A-H)
    • 145th Infantry Brigade (A-H)
  • Group Sunkel (A-H)
    • 187th Division
    • part of 144th Infantry Brigade (A-H)
    • part of Alpenkorps^[6]
  • Group Krafft
    • part of Alpenkorps
• Cavalry Corps "Schmettow"
  • 51st Honvéd Infantry Division (A-H)
  • 3rd Cavalry Division
  • 1st Cavalry Division (A-H)
• En route
  • 76th Reserve Division

• 
  Romanian invasion of Austria-Hungary, August 1916
• 
  Central Powers counterattack, September–October 1916
• 
  Operations in Romania, November 1916 to January 1917

Commanders

The original 9th Army had the following commanders until it was dissolved 30 July 1916:^[7]

A "new" 9th Army was formed in Transylvania for the Romanian Campaign on 6 September 1916. It was dissolved on the Western Front on 18 September 1918.^[9]

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.^[11]
• 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.