The most famous and detailed description of a Carolingian warrior was that of Charlemagne himself, written by a monk of Saint Gall in 773 AD: "Thus appeared the Iron King with his crested iron helm (ferreis galea christatus), with sleeves of iron mail (ferreis manicis armillatus) on his arms, his broad chest protected by an iron byrnie (ferrea torace tutalus), an iron lance in his left hand, right free to grasp his unconquered sword. His thighs were guarded with iron mail, though other men were wont to leave them unprotected so that they might spring more lightly upon their steeds. And his legs, like those of all his host, were protected by iron greaves (ocreis). His shield was of plain iron (boss and edging) without device or color."

Charlemagne preferred all his free vassals to be warriors. While this was never entirely the case, all free men were liable for military service under the royal bannum or summons. General mobilization, usually in a limited area responding to a specific crisis, was known as lantweri. While this obligation even applied to recently conquered peoples, the Franks formed the heart of his army.

Charlemagne's standing army, called the scara, provided leadership, and to some degree training, for allied and levee troupes. There were three ranks of seniority within each scara: the scholares, the scola, and the milites aulae regiae. In order to achieve and maintain their rank, Carolingian mounted soldiers had to provide their own helmet, body armor, sword, scabbard, leg defences, lance (spear), shield, and horse. The price for this required equipment totalled 44 solidi. A peasant's cow, by contrast, was worth 3 solidi. 

The spangenhelm was the most popular type of helmet. Due to strong Avar influence in the region, a mail coif or aventail would likely have bolstered head and neck defence if the warrior could afford it. The most popular body armor for heavy cavalry consisted of overlapping iron, bronze, or horn scales mounted to a leather or fabric coat. Infantry troupes often favored lighter mail or leather hauberks. Failure to wear one's brunia body armor could result in a loss of both status, and the estates which accompanied it.

Arm defences consisted of splinted iron vambraces or long mail sleeves. Similarly, leg defences meant either splinted iron greaves or long skirted mail hauberks. The aforementioned description of Charlemagne not withstanding, thigh armor was quite rare, as it was difficult (and somewhat uncomfortable) to ride without stirrups when the insides of one's legs were covered in armor.

Although mounted Carolingian forces were called "cavalry", most skirmishes were actually fought by riding to the field of battle, dismounting, and engaging the enemy on foot. Because of the weight of their armor and weapons, the Carolingian cavalry used sturdy Barb horses which had excellent endurance and speed. Mounted shock-cavalry charges, however, were extremely rare, primarily due to a lack of stirrups (which were borrowed from the Magyars and/or Avars and did not become popular until many years after Charlemagne's death). It is somewhat embarrassing, not to mention a bit painful, to fall off one's horse while charging toward the enemy.

Spears were the most common and cheapest weapon for all warriors. Because the Carolingians employed a parrying, almost fencing use for their spears, they added large horizontal lugs or wings beneath their blades. Unlike a conventional boar spear, these lugs had nothing to do with preventing over-penetration, they simply enhanced the cutting and thrusting style that was commonly employed – both from horseback and on foot. When employed by a mounted warrior, this spear was called a lance (not to be confused with the later-period weapon of the same name that was employed (couched) in a completely different fashion).

The most expensive of the soldier's weapons was his sword. Since its manufacture made the greatest demands on available technology, the sword remained an essentially noble item of equipment and was, therefore, the most noticeable outward symbol of knighthood (even more so than spurs). These pattern-welded blades took at least 200 man-hours to make, and their forging required two to three hundredweights of charcoal. Because scabbards lined with oil-soaked fur or hair helped keep these costly weapons rust free, they were also required equipment.

By Carolingian times, the old Frankish throwing axe (fransiska) had been abandoned in favor of a single edged short-sword or large dagger, called a scramasax, which was often carried in addition to required equipment.

Archery too had major tactical importance on the battle field. Foot soldiers used longbows of yew wood, while horsemen often employed roman-style double-convex composite bows. For horse archery, the Carolingians adopted the wood-framed saddles and raised pommels of their Avar foes.

The degree of training in Charlemagne's army depended on the status of the warrior. All men knew how to use some sort of weapon, as hunting was part of everyday life. Children of the nobility would be introduced early to horsemanship, and would often play with toy weapons until they were old enough to use real ones. From puberty they would practice with javelin, bow and sword. Mounted warriors also practiced using their spears as lances against a quintaine (target dummy).

Training as a unit involved war-games such as the causa exercitii in which equal forces, often from distinctive ethnic or tribal backgrounds, charged at each other, pretended to throw or wield their weapons, then turned in feigned flight with their shields protecting their backs. The opposing side would then repeat this performance. There were no real uniforms at the time, so units were often comprised people who already knew each other by sight.

Control on the battlefield was attempted using signalling trumpets. Banners were mainly used as rallying points and to indicate the direction of attack. Charlemagne's personal standard was a dragon-shaped "sock" kite. The Imperial banner, given to him by Pope Leo III, had a purple field with 28 white, eight-pointed, stars. (There is a mosaic commemorating Charlemagne's coronation as Emperor which shows him receiving this banner directly from Saint Peter, and by implication, from God). Each scara, had its own banner and was divided, in turn, into several cunei (cavalry formations of 50 to 100 men) each carrying their own colors.