# XVIII Reserve Corps (German Empire)

The XVIII Reserve Corps (German: XVIII. Reserve-Korps / XVIII RK) was a corps level command of the German Army in World War I.

## Formation

XVIII Reserve Corps was formed on the outbreak of the war in August 1914 as part of the mobilisation of the Army. It was initially commanded by Generalleutnant Kuno von Steuben, formerly of the Prussian War Academy. It was still in existence at the end of the war in the 18th Army, Heeresgruppe Deutscher Kronprinz on the Western Front.

### Structure on formation

On formation in August 1914, XVIII Reserve Corps consisted of two divisions, made up of reserve units. In general, Reserve Corps and Reserve Divisions were weaker than their active counterparts
    Reserve Infantry Regiments did not always have three battalions nor necessarily contain a machine gun company
    Reserve Jäger Battalions did not have a machine gun company on formation
    Reserve Cavalry Regiments consisted of just three squadrons
    Reserve Field Artillery Regiments usually consisted of two abteilungen of three batteries each
    Corps Troops generally consisted of a Telephone Detachment and four sections of munition columns and trains
In summary, XVIII Reserve Corps mobilised with 24 infantry battalions, 5 machine gun companies (30 machine guns), 6 cavalry squadrons, 12 field artillery batteries (72 guns) and 3 pioneer companies. It included one active Infantry Regiment (168th).
| Corps | Division | Brigade | Units |
| XVIII Reserve Corps | 21st Reserve Division | 41st Reserve Infantry Brigade | 80th Reserve Infantry Regiment |
| XVIII Reserve Corps | 21st Reserve Division | 41st Reserve Infantry Brigade | 87th Reserve Infantry Regiment |
| XVIII Reserve Corps | 21st Reserve Division | 42nd Reserve Infantry Brigade | 81st Reserve Infantry Regiment |
| XVIII Reserve Corps | 21st Reserve Division | 42nd Reserve Infantry Brigade | 88th Reserve Infantry Regiment |
| XVIII Reserve Corps | 21st Reserve Division | | 7th Reserve Dragoon Regiment |
| XVIII Reserve Corps | 21st Reserve Division | | 21st Reserve Field Artillery Regiment |
| XVIII Reserve Corps | 21st Reserve Division | | 4th Company, 11th Pioneer Battalion |
| XVIII Reserve Corps | 21st Reserve Division | | 21st Reserve Divisional Pontoon Train |
| XVIII Reserve Corps | 21st Reserve Division | | 17th Reserve Medical Company |
| XVIII Reserve Corps | 25th Reserve Division | 49th Reserve Infantry Brigade | 116th Reserve Infantry Regiment |
| XVIII Reserve Corps | 25th Reserve Division | 49th Reserve Infantry Brigade | 118th Reserve Infantry Regiment |
| XVIII Reserve Corps | 25th Reserve Division | 50th Reserve Infantry Brigade | 168th Infantry Regiment |
| XVIII Reserve Corps | 25th Reserve Division | 50th Reserve Infantry Brigade | 83rd Reserve Infantry Regiment |
| XVIII Reserve Corps | 25th Reserve Division | | 4th Reserve Dragoon Regiment |
| XVIII Reserve Corps | 25th Reserve Division | | 25th Reserve Field Artillery Regiment |
| XVIII Reserve Corps | 25th Reserve Division | | 1st Reserve Company, 11th Pioneer Battalion |
| XVIII Reserve Corps | 25th Reserve Division | | 2nd Reserve Company, 11th Pioneer Battalion |
| XVIII Reserve Corps | 25th Reserve Division | | 25th Reserve Divisional Pontoon Train |
| XVIII Reserve Corps | 25th Reserve Division | | 18th Reserve Medical Company |
| XVIII Reserve Corps | Corps Troops | | 18th Reserve Telephone Detachment |
| XVIII Reserve Corps | Corps Troops | | Munition Trains and Columns corresponding to the III Reserve Corps |

## Combat chronicle

On mobilisation, XVIII Reserve Corps was assigned to the 4th Army forming part of the centre of the forces for the Schlieffen Plan offensive in August 1914.

## Commanders

XVIII Reserve Corps had the following commanders during its existence:
| From | Rank | Name |
| 2 August 1914 | Generalleutnant | Kuno von Steuben |
| 19 August 1914 | General der Infanterie | Kuno von Steuben |
| 5 June 1917 | Generalleutnant | Karl von Wenninger |
| 11 September 1917 | Generalleutnant | Ludwig Sieger |