The decline of the Roman Empire created a vacuum of military power and force in the European countries and provinces from which Roman legions had been withdrawn. Thus, during the fifth century, after having fought and defeated the Visigoths, Burgondes and Ostrogoths and later on the Alamans, the Franks took advantage of the situation to erect their own empire. King Clovis embraced Christianity alongside several thousands of his soldiers. All over France fortifications and fortified castles were constructed, a significant modification in the art of war, which became rather static.

The Middle Ages, a thousand-year period

France entered a rather obscure era known as the Middle Ages, which lasted for one thousand years and ended with the dawn of the Renaissance, under the cultural influence of Italy.

During this period, the means and arms of Frank soldiers were relatively less advanced compared to those of the Gauls, whose forces, like before, were divided into three main components: the infantry, the cavalry and the archers. Moreover, during sieges, the technical know-how of the engineers was solicited in order to set up and deploy catapults, rams and other means which enabled the forceful penetration of the enemy’s fortifications. Footsoldiers were equipped with a sword, a shield and a double-edged axe, which they threw at the first row of enemy forces immediately an attack was launched. Cavalrymen on their part carried a spear with harpoons (angon).

At the beginning of the VIII century, under Charles Martel’s reign, the individual equipment of combatants comprised flexible breast-plates, large shields and helmets. Subsequent centuries witnessed no major change in the state of things: from the IX to the XIII century, soldiers continued to fight hand-to-hand with the same less advanced weapons, spears, arrows, etc, and the "artillery" continued to limit itself to the use of catapults, which had undergone some technical refinements though. The real lords of the battlefield were the iron-barded knights who, after destabilizing an enemy infantry, would nobly and stylishly decide the fate of the encounter by pitting their strength against each other.

During this period, whenever French armies went to war against the English, the latter always emerged victorious, the main reason being that the French knights with their unbridled foolhardiness always charged at the enemy without bothering about strategy, and also because English commanders were awfully efficient in the way they deployed their archers. While each of these archers was able to shoot six times in a minute at enemy forces, making sure a soldier or at least a horse was hit, the French on their part clumsily grappled with their anachronistic crossbow. The Crecy battle was one of the unfortunate instances where the English illustrated their supremacy.

The middle of the medieval ages was marked by the erosion of the authority of the State, which was in the hands of the landowner military nobility, and the dependence of the serfs and villains who constituted the peasantry. Religious thinking was authoritatively regimented by the Church, and any behavior considered impious or heretic was suppressed sometimes with absolute ruthlessness and cruelty in the name of exorcism.

Powder and firearms brought in a new dimension to the art of war

It wasn’t until early XIV century with the advent of the gunpowder that primitive firearms appeared and gradually began to revolutionize the art of war.
Early artillery units were equipped with pieces of ordnance, called bombards, mortars, cannons...
The first projectiles were ball-like stones, after which came iron cannonballs and finally spherical explosives.
Weapons carried around on the body were not left out in the technical evolution. The bow and the crossbow disappeared, giving way to shoulder arms like the harquebus, the musket and the rifle, which subsequently became elongated with the bayonet. As for swords and daggers, they resolutely continued to hang around the waist of combatants and sometimes in addition to pistols.

From the end of the Middle Ages to the era of modern armies

The organization of the military and its structures witnessed a significant change, and infantry units, companies, battalions and regiments had to be adapted to suit the new warring techniques which of course marked the end of the Middle Ages and ushered in the era of modern armies.