Charlemagne leaves a garrison and returns to his capitol, Aix, passing through many French cities along the way. He deposits the oliphant at a sacred site, and leaves the bodies of Roland, Oliver, and the Archbishop at the church of St. Romain. He arrives in Aix and summons his judges: the trial of Ganelon will begin soon. But first, Charlemagne must give Aude, Roland's wife, the news of his death. She dies of grief on the spot.
Ganelon, brutalized by the servants, faces the charge of treason. He argues that though he arranged for Roland's death, it was in reaction to Roland's nomination of him as envoy, which Ganelon thinks was an attempt to kill him. Though he betrayed Roland, he did not betray the king. Thirty of Ganelon's kinsmen speak for him. Among them is Pinabel, a mighty knight and gifted speaker. Pinabel is so persuasive that the judges, who are collected from all over Charlemagne's realm, are inclined to seek peace and let Ganelon go free. Charlemagne is grieved by their choice. Only Thierry, brother of Lord Geoffrey, is willing to fight for the case that Ganelon is guilty of treason.
Thierry argues to Charlemagne that "whatever Roland may have done to Ganelon, / The act of serving you should have protected him. / Ganelon is a traitor in that he betrayed him" (ll. 3827-9). Thierry is willing to fight against any who say otherwise, and Pinabel accepts the challenge. Pinabel is by far the stronger and larger man.
The men make confessions at church and return to fight. The combat is fierce. The audience is moved to weeping with worry and sorrow for the men: they quickly dehorse each other and destroy each other's shields, leaving the combat to the sword. Pinabel offers to be Thierry's vassal if they cease the combat, and let Ganelon live. Thierry refuses, and offers to reconcile Pinabel to the king, if Pinabel will stop fighting and let Ganelon die. Pinabel refuses, saying he will stand by his kinsman. They continue fighting, and, as Pinabel is stronger, he wounds Thierry badly. But Thierry is protected from death by God, and he rallies to deliver the killing blow. The Franks proclaim that God has worked a miracle. They decide to have Ganelon's thirty kinsmen executed along with him. Ganelon's kinsmen are all hanged, and he himself is drawn and quartered (each limb is tied to a horse; the horses run in opposing directions, ripping the victim apart).
Charlemagne announces that Bramimonde, having heard the gospels and the articles of Christian faith, wishes to be baptized. She is christened Juliana. That night, Gabriel appears to Charlemagne in a dream, telling him that he must aid King Vivien of Imphe, a Christian monarch besieged by pagans. His reaction is weary and sorrowful: "God,' said the king, how wearisome my life is!' / He weeps and tugs at his white beard" (ll. 4000-1). Thus the poem ends.
The final line of the poem, "Here ends the story which Turoldus relates" (l. 4002) has been translated by Glyn Burgess in a way that keeps the ambiguity of the original old French. "Relates" (or "declinet" in the original) can mean write, transcribe, or weaken, leaving it unclear what Turoldus' relationship to the work was. Any theory can only be speculation.
The kind of chivalry in The Song of Roland predates the later medieval ideas of courtly love, which have influenced our current definition of the word "chivalry." Relationships between men and women are not really explored in The Song of Roland. Roland has said almost nothing about his wife Aude; the concept of chivalry here belongs to a more warlike age. If anything, his relationship with Oliver seems to be the most important earthly relationship in his life. Companionship and equality seem to exist only between men. Aude dies of grief when she hears of Roland's death, but that tells us more about how awe-inspiring a figure Roland was than the depth of their relationship together. We can infer that they barely saw each other, as Roland has spent his adult life fighting for his uncle. Aude is so upset by the loss of this magnificent husband, that she refuses to be comforted by Charlemagne's immediate offer of another suitable knight. But not just any knight will do: Aude was apparently only happy when Roland was her (absent) husband. She is so grief-stricken that she dies even before Charlemagne has time to tell her that her brother Oliver is also dead.
At Ganelon's trial, different values are the real forces moving the decisions. On one side, there are the values of compromise and political pragmatism. Ganelon is a skilled knight, from a family that we can infer is powerful: the translator has said that the judges are "inclined to peace" (l. 3797), indicating that the execution of Ganelon might cause problems. But on the other side is the multi-faceted issue of feudal loyalty. Charlemagne has his duty to avenge his vassal, and what's more, Ganelon, if we consider the feudal code, has indeed committed treason. Thierry argues articulately that a man cannot put his personal desires ahead of the interests of the king: no matter what Ganelon's quarrel was with Roland, bringing about the death of a faithful servant of the king amounts to an attack against the king himself.
God, of course, sides with these latter arguments. The Franks never seem to doubt that a just God will intervene and provide an outcome which will make for a just verdict. And he intervenes once more, allowing victory for the smaller, weaker Thierry. Implicit in this intervention is the depth of Ganelon's sin: he has not only betrayed Charlemagne in pursuing selfish interests, he has also betrayed God and the war against Islam.
The cost for Ganelon and his family is brutal. The poet is almost gleeful as he describes the hanging of Ganelon's kinsmen and Ganelon's own horrifying execution: "A man who betrays another has no right to boast of it" (l. 3974).
Immediately afterward, we see God's hand in a more gentle one. Charlemagne announces that Bramimonde is to become a Christian. Significantly, the poet chooses near the end of the poem to give us a reminder that Christianity is not all forced conversions and dismemberment. Although modern readers might find Bramimonde's "voluntary" conversion a wee bit problematic, it is nonetheless a gentler alternative to the Holy War pursued in the rest of the poem.
It is not, however, the last word. Charlemagne's sleep that night is interrupted by another visit from the angel Gabriel. He will soon have to depart for yet another campaign against the infidel. His reaction is less than enthusiastic: he bewails the weariness of his life, weeps, and does his characteristic gesture of grief by tugging at his beard. The theme of duty, in this case duty to God, is the finishing note of the poem. War is duty. This final event confirms the idea in the poem that though God proposes, man disposes. The Franks must carry out God's will; they are his agents on earth. A Christian must submit to the will of God; implicitly, the audience should follow Charlemagne's example. Our final image of Charlemagne gives him a great deal of humanity and vulnerability. This Charlemagne is no bloodthirsty and ambitious conqueror. We see him as a tired, grandfatherly old man, obliged to set off for yet another bloody war.