After the Cold War, corps structures continued to exist for some time, but not all armed forces underwent reforms. Among the world’s leading militaries, such organisational structures are present in the armed forces of the United States (four), France (one), Greece (two and a separate logistics corps), Spain (one), Turkey (nine), the United Kingdom (one), India (fourteen), South Korea (six), and Pakistan (nine).
Even the Russian Federation, despite its outdated military strategies, has six corps: the 3rd (Nizhny Novgorod), 11th (Kaliningrad), 14th (Murmansk), 22nd (Simferopol), 44th (Petrozavodsk), and 68th (Petropavlovsk-Kamchatsky). Meanwhile, the DPRK army has 11 corps.
In other words, corps structures are neither anachronistic nor unusual.
What unites Corps?
Let’s take the US Army as a reference point.
1st Corps: Includes the 7th and 25th Infantry Divisions, the 11th Airborne Division, the 17th Field Artillery Brigade, the 42nd Military Police Brigade, the 555th Engineer Brigade, the 201st Expeditionary Military Intelligence Brigade, and the 593rd Expeditionary Support Command (which includes the 62nd Medical Brigade, the 51st Communications Battalion, and the 13th Support Battalion). Its forward command centre is deployed in Japan.
3rd Corps: Comprises the 1st and 4th Infantry Divisions, the 1st Cavalry Division, the 1st Armoured Division, the 75th Field Artillery Brigade, the 36th Engineer Brigade, the 3rd Cavalry Regiment, the 11th Communications Brigade, the 504th Military Intelligence Brigade, the 89th Military Police Brigade, and the 13th Support Command, as well as the 1st Medical Brigade.
5th Corps (deployed in Europe – Germany, Poland, and Romania): Includes the 2nd Cavalry Regiment, the 41st Field Artillery Brigade, the 12th Army Aviation Brigade, a rotating Light Infantry Division (stationed at Mihail Kogălniceanu Air Base, Romania), a rotating Support Brigade, and a rotating Armoured Division (stationed in Bolesławiec, Poland). Polish President Andrzej Duda even travelled to Washington to request that this corps remain in Poland.
18th Corps: Includes the 3rd Infantry Division, the 10th Mountain Division, the 82nd and 101st Airborne Divisions, the 3rd Support Command (Expeditionary), the 7th Transport Brigade, the 16th Military Police Brigade, the 18th Field Artillery Brigade, the 20th Engineer Brigade, the 35th Communications Brigade, the 44th Medical Brigade, and the 525th Expeditionary Military Reconnaissance Brigade.
As we can see, there are no strict standards for corps composition. The US doctrine envisions the use of battalion and brigade tactical groups, which do not have permanent personnel in combat but are instead assembled for specific missions. This flexibility extends to the organisational structure of corps, which are adapted to different combat tasks. When a corps is assigned an unexpected mission, its structure is adjusted accordingly.
A curious detail: the 5th Corps’ forward operating base (FOB) is located at Fort Knox - the same place where the United States stores its gold reserves. This base also houses the US Army Recruiting Command, the Army Training Command (akin to Ukraine’s Desna), the Army Human Resources Command, and multiple military units, including the 1st Infantry Division, the 4th Cavalry Brigade, and the 1st Sustainment Command. Even the royal regalia of the United Kingdom and the Magna Carta were stored there during the Second World War for security reasons.
Corps in the Ukrainian Armed Forces
A typical corps includes three or four divisions, along with a field artillery brigade, an engineering brigade, a communications brigade, an intelligence brigade, a military police brigade, and a medical brigade.
For the Armed Forces of Ukraine, the corps system is not entirely new. In 1994, the Soviet-era armies stationed in Ukraine were reorganised into army corps:
- 6th Corps (Dnipro)
- 8th Corps (Zhytomyr)
- 13th Corps (Rivne)
- 32nd Corps (Simferopol)
- 38th Corps (Ivano-Frankivsk)
However, financial difficulties in the early 2000s led to reductions. The 38th Corps was disbanded, and the 32nd Corps became the Coastal Defence Command in 2003. The 8th Corps was restructured into the Joint Rapid Reaction Forces, as funding for defence was so limited that only the most critical units received combat training. The 6th and 13th Corps survived until 2013, when they were transformed into the operational commands South and North.
These corps, in their 1994 format, had four to six brigades (some even included divisions before they were disbanded), along with missile and artillery brigades, an army aviation brigade, MLRS regiments, and various support units (anti-tank, anti-aircraft, engineering, reconnaissance, electronic warfare, logistics, and repair battalions).
The 2014 war prompted changes in military strategy. By 2015, a reserve corps (now the 11th Army Corps) was created. In 2023, ahead of the Zaporizhzhya offensive, the 9th and 10th Army Corpswere formed. By 2024, the 7th Air Assault Corps and the 30th Marine Corps had also been established.
Challenges Ahead
While the introduction of corps brings high expectations, several critical issues need to be addressed:
- Shortages of equipment and personnel: The planned 18 corps must be adequately equipped. Currently, Ukraine’s Defence Forces have one missile brigade, 11 artillery brigades, two MLRS brigades, and multiple regiments and battalions - insufficient to fully equip 18 corps. Key assets like pontoon and bridge parks and air defence systems cannot be evenly distributed.
- Integration of the National Guard: The National Guard of Ukraine (NGU) operates under the Ministry of Internal Affairs and is primarily tasked with law enforcement and public security. How will an artillery brigade or an anti-aircraft missile regiment fit into this structure? Should they even be included? Former Chief of the General Staff Viktor Muzhenko argues that forming NGU corps is premature and that creating divisions would be more practical. Facebook/13th Khartiia Brigade
- Operational Restructuring: The transition to a corps system requires redistributing operational zones, moving all brigades to new locations so that each corps commander leads their own forces. A strategic regrouping of this scale is extremely difficult without a strategic pause, especially with an ongoing war and uncertain US military aid.
- Command & Control Staffing: The NATO standard Field Manual FM 6-0 states that a corps command post should have at least 47 personnel at any given time, meaning a full command staff would require 70–100 officers. Ukraine will need around 1,800 experienced staff officers, which is a major challenge.
The decision to establish corps is already being implemented, but a turbulent transition period lies ahead. The key challenge will be ensuring that command structures gain operational capability without compromising the frontline. Let’s hope these changes do not disrupt Ukraine’s defence efforts.