Its field headquarters was established in January 1915.
In August 1915, the entire staff of the 12th Army was replaced by that of the 13th Army, which itself ceased to exist.
The unit was assigned to the Northwestern Front and later to the Northern Front, being disbanded by the end of 1917.
Commanders
No.
Portrait
Commander
Took office
Left office
Time in office
1
von Plehwe, PaulGeneral of Cavalry Paul von Plehwe (1850–1916)
14 January 1915
8 June 1915
145 days
2
Churin, AlekseyGeneral of Infantry Aleksey Churin [ru] (1852–1916)