|I Army Corps|
Flag of the Staff of a Generalkommando (1871–1918)
|Country||Prussia / German Empire|
|Size||Approximately 44,000 (on mobilisation in 1914)|
|Garrison/HQ||Königsberg (now Kaliningrad, Russia)|
It was established with headquarters in Königsberg (now Kaliningrad, Russia). Initially, the Corps catchment area comprised the entire Province of East Prussia, but from 1 October 1912 the southern part of the Province was transferred to the newly formed XX Corps District.
In peacetime, the Corps was assigned to the VIII Army Inspectorate, which became the 1st Army at the start of the First World War. The corps was still in existence at the end of the war, and was disbanded with the demobilisation of the German Army after World War I.
The Corps served in the Franco-Prussian War against France in 1870–1871. It saw action in the Battle of Noiseville, the Battle of Gravelotte, the Siege of Metz, the Battle of Amiens, the Battle of Hallue, and the Battle of St. Quentin, among other actions.
From formation in 1820, the Corps commanded two divisions: 1st Division and 2nd Division. These were joined by 37th Division when it was formed on 1 April 1899. 37th Division was transferred to XX Corps when it was formed on 1 October 1912.
The 25 peacetime Corps of the German Army (Guards, I - XXI, I - III Bavarian) had a reasonably standardised organisation. Each consisted of two divisions with usually two infantry brigades, one field artillery brigade and a cavalry brigade each. Each brigade normally consisted of two regiments of the appropriate type, so each Corps normally commanded 8 infantry, 4 field artillery and 4 cavalry regiments. There were exceptions to this rule:
- V, VI, VII, IX and XIV Corps each had a 5th infantry brigade (so 10 infantry regiments)
- II, XIII, XVIII and XXI Corps had a 9th infantry regiment
- I, VI and XVI Corps had a 3rd cavalry brigade (so 6 cavalry regiments)
- the Guards Corps had 11 infantry regiments (in 5 brigades) and 8 cavalry regiments (in 4 brigades).
Each Corps also directly controlled a number of other units. This could include one or more
World War I
Organisation on mobilisation
On mobilization on 2 August 1914, the Corps was restructured. The 1st and 2nd Cavalry Brigades were withdrawn to form part of the 1st Cavalry Division and the 43rd Cavalry Brigade was broken up and its regiments assigned to the divisions as reconnaissance units. The Divisions received engineer companies and other support units from the Corps headquarters. In summary, I Corps mobilised with 24 infantry battalions, 8 machine gun companies (48 machine guns), 8 cavalry squadrons, 24 field artillery batteries (144 guns), 4 heavy artillery batteries (16 guns), 3 pioneer companies and an aviation detachment.
|I Corps||1st Division||1st Infantry Brigade||1st Grenadier Regiment|
|41st Infantry Regiment|
|2nd Infantry Brigade||3rd Grenadier Regiment|
|43rd Infantry Regiment|
|1st Field Artillery Brigade||16th Field Artillery Regiment|
|52nd Field Artillery Regiment|
|8th Uhlan Regiment|
|1st Company, 1st Pioneer Battalion|
|1st Divisional Pontoon Train|
|1st Medical Company|
|3rd Medical Company|
|2nd Division||3rd Infantry Brigade||4th Grenadier Regiment|
|44th Infantry Regiment|
|4th Infantry Brigade||33rd Fusilier Regiment|
|45th Infantry Regiment|
|2nd Field Artillery Brigade||1st Field Artillery Regiment|
|37th Field Artillery Regiment|
|10th Jäger zu Pferde Regiment|
|2nd Company, 1st Pioneer Battalion|
|3rd Company, 1st Pioneer Battalion|
|2nd Divisional Pontoon Train|
|2nd Medical Company|
|Corps Troops||I Battalion, 1st Foot Artillery Regiment|
|14th Aviation Detachment|
|1st Corps Pontoon Train|
|1st Telephone Detachment|
|1st Pioneer Searchlight Section|
|Munition Trains and Columns corresponding to II Corps|
On mobilisation, I Corps was assigned to the 8th Army to defend East Prussia, while the rest of the Army executed the Schlieffen Plan offensive in August 1914. It saw action at the battles of Stallupönen, Gumbinnen, and Tannenberg, and the First Battle of the Masurian Lakes.
The Corps was still in existence at the end of the war.
- Franco-Prussian War order of battle
- German Army order of battle (1914)
- List of Imperial German infantry regiments
- List of Imperial German artillery regiments
- List of Imperial German cavalry regiments
- Order of battle at Tannenberg
- German Administrative History Accessed: 5 June 2012
- Cron 2002, p. 392
- Cron 2002, pp. 88–89
- Hermann Cron et al., Ruhmeshalle unserer alten Armee (Berlin, 1935); Bredow
- Cron et al., Ruhmeshalle
- Wegner 1993, p. 49
- Wegner 1993, pp. 84–85
- Haythornthwaite 1996, pp. 193–194
- They formed the Guards Cavalry Division, the only peacetime cavalry division in the German Army.
- War Office 1918, p. 240
- Had a third (Horse Artillery) Abteilung of three batteries of 4 guns.
- Cron 2002, p. 324
- Cron 2002, p. 323
- 4 heavy artillery batteries (16 heavy field howitzers)
- German War History Accessed: 5 June 2012
- The Prussian Machine Accessed: 5 June 2012
- Cron, Hermann (2002). Imperial German Army 1914-18: Organisation, Structure, Orders-of-Battle [first published: 1937]. Helion & Co. ISBN 1-874622-70-1.
- Ellis, John; Cox, Michael (1993). The World War I Databook. Aurum Press Ltd. ISBN 1-85410-766-6.
- Haythornthwaite, Philip J. (1996). The World War One Source Book. Arms and Armour. ISBN 1-85409-351-7.
- Wegner, Günter (1993). Stellenbesetzung der deutschen Heere 1815-1939, Bd. 1. Biblio Verlag, Osnabrück.
- Histories of Two Hundred and Fifty-One Divisions of the German Army which Participated in the War (1914–1918), compiled from records of Intelligence section of the General Staff, American Expeditionary Forces, at General Headquarters, Chaumont, France 1919. The London Stamp Exchange Ltd (1989). 1920. ISBN 0-948130-87-3.
- The German Forces in the Field; 7th Revision, 11th November 1918; Compiled by the General Staff, War Office. Imperial War Museum, London and The Battery Press, Inc (1995). 1918. ISBN 1-870423-95-X.