Battle of Valmy, 1792: the cannonade that saved the French Republic

In the summer of 1792 most of Europe expected the French Revolution to be crushed within weeks. Austria and Prussia had formed an alliance in February to restore the authority of the Bourbons, though it was France that declared war, on 20 April. An early French invasion of the Austrian Netherlands ended in an embarrassing failure. Many of the best officers had emigrated, the soldiers no longer trusted those who stayed, and the patriotic volunteers had a reputation for running at the first shot.²

In July the allied commander, the Duke of Brunswick, issued his manifesto threatening Paris with destruction if the royal family were harmed. The allied army, Prussians, Austrians, Hessians and French émigrés, invaded on 19 August. Longwy fell on 23 August and Verdun on 2 September. Meanwhile in Paris the monarchy fell on 10 August, and Lafayette, commanding the Army of the Centre, fled into Austrian hands.³

Two new generals

Two new commanders took over in mid August: Charles François Dumouriez the Army of the North, and François Christophe Kellermann the Army of the Centre. Both armies were made up largely of soldiers of the old royal army, with a sprinkling of volunteers, and above all they kept the old royal artillery, which would win the day.⁴

Dumouriez first blocked the passes of the Argonne Forest, which he called France's Thermopylae, but the allies took a weakly held pass at Croix-aux-Bois and turned his line. He fell back to Sainte-Menehould, where he still barred the best road back to Germany and to the allied supply depots, and on 19 September Kellermann joined him. The result was an odd battle: the allies, with Paris behind them, attacked eastwards, while the French faced west, between the invaders and their bases. Brunswick could have risked a dash on Paris; instead he chose to clear his line of communication.⁵

Fog, a windmill and a cannonade

Kellermann placed the larger part of the army, about 36,000 men, on a ridge west of the village topped by a windmill, with Dumouriez's 18,000 forming a second line to the east. A misty fog covered the field on the morning of 20 September. The Prussians attacked early, and Kellermann shifted his troops to the height around the mill. As the fog lifted at about noon, the guns of both sides opened a long-range duel across some 2,500 yards.⁶

The Prussians expected the raw French to break under fire. They did not. Brunswick sent his famous infantry forward, perhaps expecting the French to run once it moved, and when the French still stood, he called the attack off and the cannonade resumed. According to Nathan Jensen, the advance received so much fire that it halted after only a few hundred yards, and the French began to chant "Vive la Nation!"⁷

The exploding wagon

At about one in the afternoon a lucky Prussian shell hit an ammunition wagon behind the French line. In the huge explosion three French regiments broke and ran, but Kellermann galloped in among them and rallied them, while Dumouriez sent reinforcements to the weakened point. Brunswick made a second and slightly more determined attack; this time his infantry came within 650 yards of the French line and began to take casualties before he halted it again. At 4 p.m. he abandoned the battle. "We do not have to fight here," he is reported to have said.⁸

Neither side suffered heavily. HistoryOfWar.org gives 164 Prussian and about 300 French casualties, noting that all the published figures fall in the same low range.⁹

A new era

Among the Prussians was the poet Johann Wolfgang von Goethe, who later wrote that from this place and this day a new era of world history began. The next day, 21 September, France officially became a republic.¹⁰

For ten days the armies faced each other while Dumouriez tried to detach Prussia from the coalition. Frederick William II demanded the restoration of the monarchy, the French demanded that the Prussians leave French soil first, and the talks broke down. On the night of 30 September the allied army began its retreat, and it crossed out of France on 23 October; Verdun and Longwy were already back in French hands. The French generals did not pursue hard: their goal had been to stop the march on Paris, and they had done it.¹¹

HistoryOfWar.org calls Valmy the battle that saved the infant Republic from early destruction. Freed from the threat, Dumouriez invaded the Austrian Netherlands and won at Jemappes on 6 November, and Prussia soon turned its attention to the partition of Poland. The name Valmy is carved on the Arc de Triomphe in Paris.¹²