Schematic plan · World War I (Western Front 1918)

Battle of Aisne-Marne II

20 July 1918
France
Victory for USA

A schematic plan, generated from the statistics of the CAA Database of Battles: the armies' size and width, the hours of fighting, the plan of attack and the outcome are as recorded; the ground and the positions are not.

USA (Fr 5th, 6th, 9th & 10th Armies, 725,000 men under Gen Foch) attacked Germany (Ger 7th & 9th Armies, 400,000 men under Cr Pr Wilhelm) in France. The CAA Database of Battles records 288 hours of fighting on a front of 128 km, a frontal attack against fortified defense and delaying action, and that USA won. Losses: USA 195,000 (27%), Germany 170,000 (43%).

This plan is generated from those figures. It shows the shape of the battle the database describes: the size and width of the armies, the plan of attack and the outcome. It does not show where the units actually stood.

The armies

USA

Gen Foch

Unit	Arm	Men
USA left wing	Infantry	148,380
USA centre	Infantry	197,840
USA right wing	Infantry	148,380
USA reserve	Infantry	123,650
USA artillery (7,000 guns)	Artillery	105,000
USA armour (350 tanks)	Armour	1,750
Gen Foch	Commander	—
In this plan		725,000

Germany

Cr Pr Wilhelm

Unit	Arm	Men
Germany left wing	Infantry	82,680
Germany centre	Infantry	110,240
Germany right wing	Infantry	82,680
Germany reserve	Infantry	68,900
Germany artillery (3,700 guns)	Artillery	55,500
Cr Pr Wilhelm	Commander	—
In this plan		400,000

What the sources report

	USA	Germany
Strength, this plan	725,000	400,000
Losses, this plan	195,000	170,000

In the CAA Database of Battles

CDB90 no. 359, “Aisne-Marne Ii”, compiled for the US Army to study what decides battles. These are the figures a what-if engine can be calibrated against.

Fighting: 288 hours
Winner: the attacker
Terrain: Rolling, Mixed
Weather: Dry, Sunny, Temperate, Summer, Temperate
Defender’s posture: Fortified defense, Delaying action
Front width: 128 km (attacker), 128 km (defender)

Force	Strength	Losses	Horse	Guns	Plan and outcome
USAattacker	725,000	195,000	0	7,000	Frontal attack; Penetration
Germanydefender	400,000	170,000	0	3,700	Defensive plan; Withdrew

Attacker’s advantages morale +2 · momentum +1 · initiative +1 · air superiority +1

CDB90 (US Army Concepts Analysis Agency, 1990), tidy edition by Jeffrey B. Arnold; data under ODC-BY 1.0.

Notes

On this reconstruction

Generated automatically from the statistics in CDB90. Frontages, depths, distances, the order of events and the terrain are schematic: they follow the recorded strengths, front widths, hours of fighting, tactical plan and outcome, not maps or accounts of the battle. The sources give no hours; the timing is conjectural.

Sources

US Army Concepts Analysis Agency; tidy edition by Jeffrey B. Arnold, CAA Database of Battles (CDB90), no. 359 · ODC-BY-1.0Strengths, losses, front widths, hours of fighting, tactics and outcome.

Facts gathered from Wikidata (CC0), Wikipedia (CC BY-SA 4.0) and Wikimedia Commons (licence per file); the plan and its text are timeastra’s own.