12th Army (German Empire)

[1] It served exclusively on the Eastern Front and was dissolved on 9 October 1916 when its commander, General der Infanterie Max von Fabeck, was transferred to 8th Army.

[2] On 9 February 1915 Guards Reserve Corps was redesignated Armee-Gruppe Gallwitz.

On 22 July, the armies of Central Powers crossed the Vistula river.

In August, the Russian Fourth Army left the Ivangorod fortress.

With the continuing Russian retreat, Warsaw became isolated, and the 12th Army seized the opportunity and conquered it on 4–5 August.

Russian withdrawal in 1915