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] 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.