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After mobilisation in the event of war the chain of command of the Imperial Russian Army ran from Stavka, the Russian general headquarters, which was created during mobilization, to Front-level (Army group) also created during mobilization, to the Army level. Army headquarters were created during mobilization by transformation of the military district headquarters. Below Army level the chain was the same as in peace-time; corps (or Army corps (terms used interchangeably), division, brigade, and regiment.
Located in Saint Petersburg and surroundings — Pushkin, Petergof and Gatchina, excepted the 3rd Infantry Division (3 ID) and the Independent Cavalry Brigade (ICavBr), located in Warsaw and subordinated to the XXIII AC
Ėmmanuelʹ, V. A. (2013). The Russian Imperial Cavalry in 1914 (First Winged Hussar Publishing ed.). Point Pleasant, NJ: Winged Hussar Publishing LLC. ISBN978-0988953215.
Deyo, Daniel C. (2016). A Compendium of the Russian Army in the First World War (Legions of the East ed.). Great Falls, VA: Counterintelligence Consulting LLC. ISBN9781540399311.
Further reading
Florinsky, Michael T. "The Russian Mobilization of 1914," Political Science Quarterly (1927) 42#2 pp. 203–227 in JSTOR
Articles relating to the Russian Imperial Army in World War I