The order of the battle of the French Army in August 1914 was planned according to the mobilisation and concentration Plan XVII and applied on 2 August 1914, the day before the German Empire declared war. The order of battle is similar to the German Army with several armies each having army corps of two infantry divisions, with a number of reserve units at the disposal of the Commander in Chief and Minister of War. The organisation changed during August with the assignment of new reserve units and the creation of new armies.

Organisation Peacetime Organisation The peacetime army had, in the spring of 1914, a strength of 882,907 men, with 686,993 in metropolitan France, 62,598 in Algeria and Tunisia, 81,750 in Morocco, and 51,566 auxiliaries.

The territory of the French Republic was divided into 21 military regions, 20 in metropolitan France, and one in Algeria (the 19th). Each region provided two infantry divisions, except the 6th which had three divisions.

The army had 686 infantry battalions. Metropolitan France had 173 infantry regiments, each with three battalions (nine regiments had four), as well as 31 light infantry () battalions, and 12 colonial infantry regiments (each with three battalions). In the colonies, there was four regiments of Zouaves with six battalions, 9 regiments of Algerian riflemen () with 40 battalions, 2 regiments of the Foreign Legion with six battalions, 5 battalions of African light infantry, 6 Moroccan colonial marching regiments, and 5 battalions of Moroccan auxiliaries.

The cavalry had 378 squadrons, organised into 89 regiments (each with four squadrons): 12 cuirassier, 32 dragoon, 21 light horse (), 14 hussar, 6 African light horse, and 4 Spahis.

The artillery had 855 batteries (each of four guns), organised into 62 field artillery regiments, 2 mountain artillery regiments, 11 foot artillery regiments, 5 heavy artillery regiments, 10 African artillery groups, and 3 colonial artillery regiments. It provided 42 divisional artillery (with three groups or nine batteries), 20 corps artillery (with four groups or twelve batteries), and 10 horse groups (with three batteries).

Mobilisation

The French army began mobilising on August 2, 1914 according to Plan XVII. The 680,000 peacetime troops were joined by 2,900,000 reservists and territorials. The three youngest classes of reservists were used to bring active units up to wartime strength, while new units were created from older reservists and territorials.

Each of 21 military regions provided an army corps of two infantry divisions. Each corps was numbered after the military region it was created from. The 19th region in Algeria did not form a corps, but did send its two divisions. A total of 46 infantry divisions were mobilised with 1,054,000 men, and 10 cavalry divisions with 52,500 men.

Each infantry division is composed of two infantry brigades with two regiments, plus a cavalry squadron, an artillery regiment (with three groups) and an engineer company. Each cavalry division is made up of three brigades with two regiments, plus a cyclist group, an artillery group and a detachment of cyclist engineers. Each army corps is made up of two infantry divisions (except the 6th corps with three divisions) with corps troops of a cavalry regiment (with four squadrons), an artillery regiment (with four groups), and an engineering battalion (with four companies).

Then, reserve infantry regiments are formed from the active regiments. They are given the same number as the active regiment plus 200. Reserve infantry regiments had two battalions, compared with three for the active regiments. These are grouped into 25 reserve infantry divisions numbered from 51 to 75 (numbered after their military region plus 50). These reserve divisions had a total of 450,000 men.

The active and reserve regiments are each created from roughly 50/50 active and reserve personnel. To show this continuity, the active battalions were numbered 1, 2, and 3, while the reserve battalions were numbered 5 and 6.

The oldest were placed into territorial infantry regiments with three or four battalions, some of which were used to create 12 territorial infantry divisions with 184,600 men.

The wartime army increased to: 1,525 infantry battalions (642 active, 406 reserve and 410 territorial), of approximately 1,100 men (with four companies of 254 men); 545 cavalry squadrons (316 active, 176 reserve and 37 territorial) of approximately 120 men (in four platoons of 30 cavalrymen); 1,468 artillery batteries (1,042 active, 265 reserve and 161 territorial), each of four guns (a group usually has three batteries); 508 engineering companies and detachments.

Added to the 95 active, reserve and territorial divisions with 1,681,100 men are the army troops of 187,500 men, garrisons of 821,400 men, depots of 680,000 men, and railway guards of 210,000 men.

Order of Battle — First-line Units Armies deployed north to south

Fifth Army

The Fifth Army () was commanded by General Charles Lanrezac. In August 1914 it was concentrated between Hirson and Dun-sur-Meus, with the mission of guarding the border with Belgium. Its strength on mobilisation was 8,886 officers, 290,464 NCOs and men, and 108,360 horses organised into five corps of ten infantry divisions, two reserve infantry divisions, and one cavalry division.

Army troops 1st Heavy Artillery Regiment Two groups (seven batteries) of 155mm CTR Two groups (six batteries) of 120mm Baquet 4th Heavy Artillery Regiment One group (four batteries) of 120mm Long 9th Telegraph Engineer Company Radio Detachment G, 7th Engineer Regiment Pontoon Engineer Company 24/2, 7th Engineer Regiment Aviation Squadrons DO 4, DO 6, C.11, N 12, REP 15, and V 24

52nd Reserve Infantry Division Commander: Hyacinthe Clément Justin Coquet 103rd Infantry Brigade 291st Infantry Regiment (reserve) 347th Infantry Regiment (reserve) 348th Infantry Regiment (reserve) 104th Infantry Brigade 245th Infantry Regiment (reserve) 320th Infantry Regiment (reserve) 5th and 6th Squadrons, 21st Dragoon Regiment 17th Field Artillery Regiment (one group) 29th Field Artillery Regiment (one group) 42nd Field Artillery Regiment (one group) Companies 2/13, 2/19, and 2/24, 1st Engineer Regiment Transmission Detachment, 8th Engineer Regiment

60th Reserve Infantry Division Commander: Géraud Réveilhac 119th Infantry Brigade 247th Infantry Regiment (reserve) 248th Infantry Regiment (reserve) 271st Infantry Regiment (reserve) 120th Infantry Brigade 202nd Infantry Regiment (reserve) 225th Infantry Regiment (reserve) 336th Infantry Regiment (reserve) 5th and 6th Squadrons, 24th Dragoon Regiment 7th Field Artillery Regiment (one group) 10th Field Artillery Regiment (one group) 50th Field Artillery Regiment (one group) Companies 10/13, 10/19, and 10/24, 1st Engineer Regiment Transmission Detachment, 8th Engineer Regiment

4th Cavalry Division Commander: Abonneau 3rd Cuirassier Brigade 3rd Cuirassier Regiment 6th Cuirassier Regiment 4th Dragoon Brigade 28th Dragoon Regiment 30th Dragoon Regiment 4th Light Cavalry Brigade 2nd Hussar Regiment 4th Hussar Regiment 4th Cyclist Group, 19th Light Infantry Battalion 4th Group, 40th Field Artillery Regiment Cyclist Engineers, 9th Engineer Regiment

I Corps Commander: Louis Franchet d'Espèrey

Corps troops 201st Infantry Regiment (reserve) 284th Infantry Regiment (reserve) 6th Light Horse Regiment 41st Field Artillery Regiment 1st Foot Artillery Regiment Companies 1/3, 1/4, 1/16, and 1/21, 3rd Engineer Regiment

1st Infantry Division Commander: Marie Alexandre Gallet 1st Infantry Brigade 43rd Infantry Regiment 127th Infantry Regiment 2nd Infantry Brigade 1st Infantry Regiment 84th Infantry Regiment 5th Squadron, 6th Light Horse Regiment 15th Field Artillery Regiment Company 1/1, 3rd Engineer Regiment

2nd Infantry Division Commander: Henry Victor Deligny 3rd Infantry Brigade 33rd Infantry Regiment 73rd Infantry Regiment 4th Infantry Brigade 8th Infantry Regiment 110th Infantry Regiment 6th Squadron, 6th Light Horse Regiment 27th Field Artillery Regiment Company 1/2, 3rd Engineer Regiment

II Corps Commander: Augustin Gérard

Corps troops 272nd Infantry Regiment (reserve) 338th Infantry Regiment (reserve) 19th Light Horse Regiment 29th Field Artillery Regiment Companies 2/3, 2/4, 2/16, and 2/21, 3rd Engineer Regiment

3rd Infantry Division Commander: Charles Louis Jacques Régnault 5th Infantry Brigade 72nd Infantry Regiment 128th Infantry Regiment 6th Infantry Brigade 51st Infantry Regiment 87th Infantry Regiment 5th Squadron, 19th Light Horse Regiment 17th Field Artillery Regiment Company 2/1, 3rd Engineer Regiment

4th Infantry Division Commander: Charles Rabier 7th Infantry Brigade 91st Infantry Regiment 147th Infantry Regiment 8th Infantry Brigade 45th Infantry Regiment 148th Infantry Regiment 87th Infantry Brigade 120th Infantry Regiment 9th Light Infantry Battalion 18th Light Infantry Battalion 16th Dragoon Regiment (two squadrons) 30th Dragoon Regiment (one squadron) 42nd Field Artillery Regiment (four batteries) Company 2/2, 3rd Engineer Regiment

III Corps Commander: Henry Sauret

Corps troops 239th Infantry Regiment (reserve) 274th Infantry Regiment (reserve) 7th Light Horse Regiment 11th Field Artillery Regiment

5th Infantry Division Commander: Élie Verrier 9th Infantry Brigade 39th Infantry Regiment 74th Infantry Regiment 10th Infantry Brigade 36th Infantry Regiment 129th Infantry Regiment 5th Squadron, 7th Light Horse Regiment 43rd Field Artillery Regiment Company 3/1, 3rd Engineer Regiment

6th Infantry Division Commander: Georges Bloch 11th Infantry Brigade 24th Infantry Regiment 28th Infantry Regiment 12th Infantry Brigade 5th Infantry Regiment 119th Infantry Regiment 6th Squadron, 7th Light Horse Regiment 22nd Field Artillery Regiment Company 3/2, 3rd Engineer Regiment

X Corps Commander: Gilbert Desforges

Corps troops 241st Infantry Regiment (reserve) 270th Infantry Regiment (reserve) 13th Hussar Regiment 50th Field Artillery Regiment

19th Infantry Division Commander: Gaëtan Bonnier 37th Infantry Brigade 48th Infantry Regiment 71st Infantry Regiment 38th Infantry Brigade 41st Infantry Regiment 70th Infantry Regiment 5th Squadron, 13th Hussar Regiment 7th Field Artillery Regiment Company 10/1, 6th Engineer Regiment

20th Infantry Division Commander: Elie Boë 39th Infantry Brigade 25th Infantry Regiment 136th Infantry Regiment 40th Infantry Brigade 2nd Infantry Regiment 47th Infantry Regiment 6th Squadron, 13th Hussar Regiment 10th Field Artillery Regiment Company 10/2, 6th Engineer Regiment

XI Corps Commander: Joseph-Paul Eydoux

Corps troops 293rd Infantry Regiment (reserve) 317th Infantry Regiment (reserve) 2nd Light Horse Regiment 28th Field Artillery Regiment 3rd Foot Artillery Regiment Companies 11/3, 11/4, 11/16, and 11/21, 6th Engineer Regiment

21st Infantry Division Commander: René Radiguet 41st Infantry Brigade 64th Infantry Regiment 65th Infantry Regiment 42nd Infantry Brigade 93rd Infantry Regiment 137th Infantry Regiment 5th Squadron, 2nd Light Horse Regiment 51st Field Artillery Regiment Company 11/1, 6th Engineer Regiment

22nd Infantry Division Commander: Joseph Pambet 43rd Infantry Brigade 62nd Infantry Regiment 116th Infantry Regiment 44th Infantry Brigade 19th Infantry Regiment 118th Infantry Regiment 6th Squadron, 2nd Light Horse Regiment 35th Field Artillery Regiment Company 11/2, 6th Engineer Regiment

Fourth Army