Joyeuse is the ceremonial sword associated with Charlemagne in French royal memory and used in later coronation ritual.
Joyeuse is the sword kept among the French royal regalia and used in the coronation of French kings, held today in the Louvre. Tradition identifies it as the sword of Charlemagne.
The object and the tradition have to be separated at the outset. The sword in the Louvre is real, and it is a genuine piece of medieval regalia with a documented ceremonial history; the attribution to Charlemagne is a claim made long after his death and is not supported by the object.
Its importance is as a coronation object rather than as a weapon. For centuries it was the physical instrument by which French kingship connected itself to the Carolingian past, and that function is entirely historical whatever the sword's origin.
The sword is a composite, assembled from parts of markedly different dates — which is normal for regalia, since pieces were repaired, replaced and reset over centuries of ceremonial use.
The pommel is the earliest element, generally dated to the tenth or eleventh century, and is of a form found in Scandinavian and northern European work. The quillons are cast as winged creatures and are usually dated to the twelfth century.
The grip and the scabbard are considerably later. The blade itself has been dated variously and the question is not closed, and the gold, the fleur-de-lis decoration and the surviving scabbard belong largely to the later medieval and early modern refurbishments.
No part of the sword has been securely dated to Charlemagne's lifetime, which ended in 814. The earliest component is at least a century later, which by itself rules out the traditional attribution as it is usually stated.
The documented history begins much later. The sword is recorded in the royal treasury at Saint-Denis, and its use in coronations is attested from the thirteenth century, which is where its verifiable career starts.
The honest summary is that Joyeuse is a genuine medieval object of composite date, associated with Charlemagne by a tradition that grew up long after him, and that the association is a fact about French royal ideology rather than about the sword.
The literary Joyeuse belongs to the Song of Roland and the chansons de geste, where Charlemagne's sword is given a name, a history and miraculous properties — a fragment of the Holy Lance in its pommel among them.
None of that describes the object in the Louvre, and it was written down in the eleventh and twelfth centuries, three hundred years after Charlemagne. The literary sword and the physical sword are separate subjects that share a name.
The identification of the regalia sword with the epic one was useful precisely because it was believed. A Capetian or Valois king crowned with Charlemagne's sword was making a claim about legitimate descent, and the sword's value lay in what it asserted.
French kings were crowned at Reims, and Joyeuse was carried in the ceremony and girded on the new king as part of the ritual that made him a king — a physical act of investiture rather than a display of an heirloom.
The regalia were kept at the abbey of Saint-Denis, the burial church of the French kings, and Joyeuse sat among a group of objects — crown, sceptre, hand of justice — whose collective purpose was to anchor the monarchy in a continuous sacred past.
It was used in coronations through to that of Charles X in 1825, which gives it one of the longest documented ceremonial careers of any surviving European object.
The sword passed from Saint-Denis into the royal collections and survived the French Revolution, when a great deal of the regalia was destroyed or broken up for its materials.
It is now in the Louvre, in the department of decorative arts, displayed with the surviving French crown jewels. Its continuous documented presence in the regalia from the medieval period is a large part of what makes it valuable.
Its composite construction is itself the provenance record. The successive components are the physical trace of centuries of repair and reuse, and reading them is how the object's real history is recovered.