Raised by the King, the compagnies d'ordonnance were a part of the French army reforms of the 1440s, which eventually lead to the French victory at Castillon in 1453, and the conclusion of the Hundred Years' War. The origins of this name is often attributed to the order or "ordenance", act of arranging, by the King of France Charles VII in 1447 for a permanent body of cavalry.
The compagnies themselves were the direct result of the so-called Grande Ordonnance of 1445, promulgated under the name of King Charles VII of France. While traditional historiography has force comprising 20 compagnies of 100 lances each, this is not the case, and is a later (even folk-historical) assessment. The sizes and numbers of companies varied. Individual companies contained anytwhere from 30 to 100 lances, depending on the defense and security requirements of the region where the troops were stationed. Prior to this legislation, the French depended on a haphazard mixture of volunteers, mercenaries, and feudal levies, of very mixed capabilities. Worse, many of these fighters were essentially freebooters, more interested in larceny or brigandage than in actually defending France. The Grande Ordonnance was a coherent, centralized effort to place the defense of the realm in the hands of a reliable force, whose senior officers were (as direct appointees of the crown) loyal to the French monarchy, and dependent on it for supplies, pay, and support.
Each lance (properly a lance fournie or 'funished' or 'equipped lance') contained, as contemporary sources put it, six horses and four men. Actually, each lance contained six personnel, each with a horse, but only four of them were counted as combat personnel. The senior member was a man-at-arms (gen d'armes in French, plural gens d'armes or gendarmerie as a collective noun). This man was supported by a squire (ecuyer or coutillier, usually a younger man still udnergoing his apprenticeship to arms, or not yet fully proved in battle. The man-at-arms and squire were further assisted by a page, or valet de guerre, usually a teenage male, who was responsible for caring for their armor, equipment, and horses. The squire was generally fully armored, and usually charged alongside (or close by) the man-at-arms, and helped him handle the sixteen- to nineteen-foot lance when they fought dismounted (which happened fairly often).
The lance further contained two archers, who were at first considered mounted infantrymen, provided with horses for mobility alone, but not for battlefield operations. Some were apparently equipped with bows and arrows, others with crossbows, and all also carried swords or axes and some armor, if usually less less than the man-at-arms and the squire. As time went on, their role became increasingly difficult to distinguish from that of the other two combat soldiers. In his famous Commentaires, the sixteenth-century soldier Blaise de Monluc noted that he had joined the army as an archer in the compagnies about 1521, but "since then everything had become degraded," and the old standards no longer applied. Monluc wrote his Commentaires in semi-retirement in the late 1560s, more than a century after the institution was created, so his assessment may well have been correct. Initially though, the archers also shared the support and assistance of their own page or valet de guerre, whose role was to provide them with the same assistance as the other such individual provided to the man-at-arms and squire.
Most men-at-arms and squires were drawn from the landowning gentry and aristocracy, although not necessarily titled nobility. This tendency became more pronounced as time went on, and the companies gradually grew more 'arristocratic' in character. The archers were more typically commoners at first, in part to integrate the considerable pool of experienced soldiers who were not gentry or aristocracy, into the framework of the new army. The men-at-arms and squire were both mounted on heavy war-horses (destriers), and full-equipped with plate armor and visored helmet. The archers were generally less well-armored, and typically mounted on decent riding horses. They were not at first expected to engage in mounted combat, but that distinction later faded, and the archers became nearly indistinguishable from the man-at-arms, as did the squire. As non-combatants, the two pages were not generally armored, and ared only with a dagger or small sword for personal protection. The pages' horses, like those of the archers, were not warhorses. The status of the pages remained largely unchanged throughout the development of the compagnies d'Ordonnance.
This professional army was supported by a new class of militia, the Francs-Archers, following the edict of the 28th of April 1448 by the same King. The francs-archers were not paid, but were exempted from taxes in recognition fo their service. As volunteers and part-time soldiers, they were often drawn from the military fraternities which existed at the time in many French municipalities. As a militia, their standards of equipment and training were very uneven, and despite some earenst effort, the francs-archers never enjoyed much success as a military force.
References: Allmand, C.T., ed. War, Literature, and Politics in the Late Middle Ages/ Liverpool, University of Liverpool Press, 1976 Burne, Alfred H. The Agincourt War. London, 1956 Contamine, Philippe. Guerre, Etat et Societe a la fin du Moyen Age. Paris, 1972 Monluc, Blaise de. Commentaires. Vale, Malcolm G. A. War and Chivalry: Warfare and Aristocratic Culture in England, France, and Burgundy at the End of the Middle Ages. Athens, University of Georgia Press, 1981