The mighty Emperor of the Franks, Charlemagne, has been fighting the Moors in Spain for seven long years. In the devastating war he has won lots of Spanish castles from them. His faithful army was undefeatable, sieging even the strongest fortresses and defeating the biggest armies. Only one of his enemies still doesn’t want to bow before his power: the ruler of Saragossa, king Marsile. The last battle for Saragossa awaits both armies and Charlemagne is preparing for it.
Marsile gathers a council of his own people and Moors and asks them for advice on how to evade the defeat. The wisest of the Moors remain silent, for they know that Charlemagne has conquered much more powerful lands and no one of his enemies managed even to slow him down. But one of them, the knight named Blancandrin, speaks up saying that the common mistake of all the previous enemies of the Franks was that they tried to fight honestly. He proposes a treacherous plan: to pretend that Marsile is ready to convert to Christianity and sign a truce to save his life. Marsile has to send the messengers with rich gifts and with an oath of peace and friendship, showing his loyalty to Franks. The ambassador should deliver to the Emperor seven hundreds of camels and four hundreds of mules loaded with gold and silver, so Charlemagne will be able to pay his army and reward his faithful knights. When the Emperor goes away with the gifts, Marsile shall swear that he will come to Aachen, the capital of his empire and in the day of St. Michael will convert to Christianity. With the gifts, the nobility of Saragossa shall send their children as hostages. They all are destined to die, of course, when the treason will be revealed. Charlemagne will go away and dismiss his army, paying them with Moors’ gold. At the day of St. Michael it will be too late for him to gather it again. So the lives of the child hostages and gold are the acceptable price for saving the throne for Marsile.
Marsile agrees with the advice of Blancandrin and gathers a great caravan with gifts to be sent to Charlemagne. He promises to every ambassador to grant them new lands for the risk they take. They all take the olive branches as a symbol of peace they seek and set up on their journey to the fruitful garden near Cordova, where Charlemagne celebrates his recent victory. He feasts and plays dice and chess among his vassals and knights. When the ambassadors arrive there they see him sitting on the golden throne, proud and handsome, with beard whiter than snow and white wavy hair laying on his shoulders. The ambassadors greet the Emperor and present him all the gifts from Marsilius, telling Charlemagne everything according to the plan. The Emperor listens them attentively and answers that he has to think over their proposal.
While the ambassadors are waiting outside, Charlemagne gathers his own council in his tent. He wants to know the opinion of barons: whether he can trust Marsile, who swears to become his obedient and faithful vassals. The barons are tired of long campaigns and heavy battles, they want to return home faster, to their lands, families and comfort of their castles. But no one can openly advice this to the Emperor, because everyone knows that Marsile is not the man that can be trusted. All of them keep silent. Only one of them, the young nephew of the Emperor, the young Roland steps forward and openly asks Charlemagne not to believe the words of the deceitful king of Saragossa. Roland reminds that Marsile betrayed the Franks before, he also promised to faithfully serve to Charlemagne, but broke his promise and betrayed him, killing his ambassadors, the glorious and noble knights Bazan and Basil. Roland begs Charlemagne to siege the rebellious Saragossa in the name of Bazan and Basil and avenge their death.
The Emperor is still silent, but the barons are very displeased with the proposal of Roland. Ganelon, Roland’s stepfather, is one of them. Now it’s his turn to speak and he speaks about what he sees: the army is tired already, so many battles are won that they may afford themselves to skip the very last one - especially because now they already have the money to pay the army fully. There is no reason not to believe the Moors: they have no choice but to obey Charlemagne. His speech gets much more support. One of noble barons, Nemon of Bavaria, one of the most trusted knights, advises the Emperor to listen to the Ganelon’s words and agree to Marsile’s proposal. He reminds that it is a duty of any good Christian to forgive their enemies and be merciful to the infidels who want to convert, because turning them to the true faith is also the Christian duty. Nemon is sure that all the Moors will arrive on St. Michael’s day to Aachen and convert.
Charlemagne turns to all his knights and asks who trusts Marsile enough to go to Saragossa with an answer. Roland is ready to serve his Emperor and take the risk, even despite his advice is declined, but Charlemagne doesn’t want to risk his brave knight and beloved nephew. Nemon also volunteers, but the Emperor needs him in the camp. Many barons agree to go, only Ganelon is silent. Then Roland suggests Ganelon to go, because he is the one who decided to trust Marsile. Ganelon looks at him with fear, but the rest of the council nod their heads in agreement: it sounds reasonable and fair.
Ganelon calls Roland out for such a proposal, accusing him of an old hatred, as he is Roland’s stepfather. Ganelon says that Roland has long wanted to destroy him and now he had the chance, taking advantage of the opportunity, to send him to certain death. Ganelon pleads Charlemagne to care for his wife and children after the Moors will kill him and laments that he will not see his beloved France anymore. The Emperor is furious with such a cowardice and orders him to go immediately, handing him his glove as a sign of his ambassadorial authority. Ganelon’s hands are trembling and he drops the glove to the ground that is seen as a bad omen. The Franks understand that they chose the wrong person to go, but no one can change the fate so they decide to obey God and accept everything that will come.
Ganelon goes into his tent and chooses the heavy battle armor for his mission. He leaves the camp and soon he meets the embassy of the king Marsile waiting for the answer. The head of the embassy is Blancandrin, the author of the cunning plan. Ganelon and Blancandrin have a long conversation. Blancandrin, pretending to be marvelled with the success of Frank army, asks Ganelon about the secret of their victories. Embittered, Ganelon tells that Roland, his hated stepson, leads the elite troops that can turn the tide of the battle. That’s why Roland is so loved by the Emperor and the rest of the army. Blancandrin, sensing the rivalry between the stepfather and stepson, slowly persuades Ganelon to betray his Emperor out of hate to Roland and feeling of injustice towards himself. So when the embassy is near the gates of Saragossa, Ganelon and Blancandrin give each other an oath to do anything to destroy Roland.
Ganelon is led to the king of Saragossa. Bowing to the king, Ganelon recites him the message of Charlemagne. The Emperor agrees to let Marsile live, but on St. Michael’s day he is waiting for the king in Aachen. If Marsile dares to disobey him or break his promise, he will be delivered to Aachen in chains and painfully and publicly executed there. Marsile, not expecting such a sharp and humiliating response, grabs a spear, wishing to kill Ganelon on the spot, but Ganelon dodges a blow and steps aside. Blancandrin turns to Marsile and whispers to him asking to listen further.
Ganelon approaches Marsile’s throne again and continues his speech. He says that the king has no reasons to be angered. Charlemagne only wants that Marsile accepts the Christian faith. If he does so the Emperor will give him the half of Spain. But the other half shall go to his nephew, the arrogant Roland. Roland is the one guilty of killing other Moor armies, so he will be a bad neighbor to them, he will seize Marsile’s land and oppress his people in every possible way. All the troubles are from Roland alone and if Marsile wants peace in his new country then he shall not only obey the Emperor but somehow get rid of his nephew.
Marsile is finally pleased with what he hears. But he has no idea how to deal with Roland, so he asks Ganelon to come up with the plan. If Ganelon, with the aid of the Moors, will manage to destroy Roland, Marsile promises him the rich gifts and the new castle in the beautiful part of Spain for his faithful service. Ganelon already has the plan, he had the time to think it over on his way to Saragossa. He knows for sure that Charlemagne will leave someone in Spain to ensure peace on the conquered lands. The Emperor will definitely ask Roland to stay, with a relatively small squad and alone - without the support of the army of the Franks. Marsile will defeat Roland and his troops, killing the best vassal of the Emperor. Marsile agrees with the plan. He invites Ganelon to his chambers and orders to bring there expensive gifts, the best furs and jewellery that his new friend will present to his wife in distant France. Soon Ganelon is escorted back, as it was agreed. Every noble Moor gives an oath of peace and sends one of his children to Charlemagne as hostage.
At the dawn Ganelon arrives to the camp of the Franks and immediately goes to the Emperor. He reports that he brought lots of gifts and hostages but what is most important - Marcile gave away the keys to Saragossa. The Franks rejoice. Charlemagne orders his army to break camps and prepare for the journey home. The brutal war is over. But, as Ganelon predicted, the Emperor doesn’t want to leave his new land unprotected. Otherwise he will not be able to reach France without a riot behind his back. In this case everything they fought for the seven years would be in vain. Ganelon advises Charlemagne to leave the glorious Roland with a detachment of brave warriors who will defend the honor of the Franks if someone dares to go against the will of the Emperor. Roland, hearing this words from Ganelon, rushes to the Emperor and thanks him for this appointment. He says that he is not afraid, unlike Ganelon, to die for France and the Emperor himself, even if he will fight alone.
Suddenly the iron-willed ruler covers his face with his palms and starts to cry. He doesn’t want to part with Roland, he feels something ominous coming. But Roland is already gathering his devoted friends who will stay with him, covering the retreating army. The first ones to volunteer are Gauthier, Odon, Jerin, Archbishop Turpin and the glorious knight named Oliver. With a heavy heart Charlemagne leaves Spain, bowing to Roland as a sign of honor. He feels they are destined to meet no more.
Roland, having gathered his troops, descends into the nearest gorge that is very suitable to defend. He hears the drums and watches the people leaving for home. The time passes and the Frank army is already far away. Roland and Oliver climb the high hill and see hordes of Moors advancing to them. Oliver curses the treacherous Ganelon and begs Roland to blow the horn. Charlemagne can still hear it and turn the army back. But the proud Roland doesn’t want any help and asks his soldiers to go fearlessly into the battle and win.
Once again Oliver ascends to the hill and sees that the Moors are very close and their army grows and grows. He again pleads Roland to blow the horn and call for aid. Roland refuses again in his vanity, calling the very offer a shame to Oliver. Some more time passes and for the third time Oliver begs Roland, now falling to his knees in front of him and asking him to think not only about his honor but about the lives of people he brought with him. Roland doesn’t want to listen. He gathers his troops and with the battle cry rushes towards the oncoming Moor forces.
The horrible massacre lasts for hours. The Franks are still standing, slaughtering the Moors. The screams and the ringing of weapons are echoing in the gorge. Oliver rushes through the battlefield with a wreck of a spear: he hit too many Moors with it. The squad of Roland is fighting like lions, but unlike the Moors they do not have reinforcements. The Moors, on the contrary, are waiting for the main army, led by king Marsile himself. Only seeing the king, Roland finally understands the vile betrayal of his stepfather.
When Marsile’s army is engaged into battle, the young Franks, his friends, fall one by one. Roland, eaten alive by guilt, is searching for Oliver on the battlefield: now he is ready to blow the horn. But his friend says that it is too late now. The Emperor is too far already and won’t hear anything. Oliver turns away and returns to the battle. But Roland is determined to try. He takes his horn and blows, his mouth covered in blood from the impossible attempt - and the horn sounds as loud as it can possibly sound.
Even at the border of France Charlemagne hears the sound of Roland’s horn and understands that his bad feelings were not in vain. The Emperor immediately turns the army back and rushes to the aid, knowing that most likely he will arrive to see only the dead bodies.
Meanwhile, Roland looks with remorse at the bodies of his friends who died because of his vanity and pride. The knight falls to the ground crying and asking forgiveness for what he has done. But still the battle is not over and, calming himself, he returns to the fight. He kills many noble Moors with his sword Durandal, avenging the deaths of his friends. Finally he faces Marsile, the king of Saragossa himself. Roland rushes through his guard, kills his son, but Marsile flees from the battlefield.
It is dusk, but Franks are still standing. One of the Moors strikes Oliver in the back with the spear. Roland sees it and understands that his best friend is slain too. He seeks Archbishop Turpin on the battlefield but sees that he is left alone: his army is dead. The day comes to an end and the twilight covers the bodies of valiant Franks.
Roland is exhausted, his face is covered in blood. His eyes are darkened, the knight is almost blind from fatigue. He falls on the grass, closes his eyes and thinks about France in his very last moments. At night one of the Moors finds him, still breathing, and finishes him off. The army of Charlemagne finds him at dawn. The Emperor falls to his knees in front of his nephew’s body and tearfully swears to avenge him. The troops rush forward to chase the Moors and give them the final fight.
The wounded Marsile hides behind the high walls of Saragossa. He hears the battle cries of the Franks entering the city. No one of his neighbors sent him troops to help, now the treacherous king is alone against his destiny. He finally exits the tower to give the Emperor the last fight and is defeated and killed. Charlemagne gathers the bodies of the fallen Franks and returns to his homeland to properly bury the heroes.
The whole France mourns the great warriors. Roland was loved by people as a brave knight and wise ruler. Everyone who knows about Ganelon’s betrayal demands his execution. Some of them go as far as asking to kill all his family too. But Charlemagne doesn’t want to execute his vassal without giving him a chance to explain himself. One of his counselors, Thierry, offers to leave God to decide. He is ready to fight in a duel with Ganelon’s relative named Pinabel. The stake will be Ganelon’s life. If Thierry wins, Ganelon will be executed, if not, he will live. The Emperor agrees.
The noble Franks greet each other before the duel and raise their swords. They fight for a long time, but no one can defeat the other. Thierry is heavily wounded but when everyone expect him to collapse, he raises his sword and finishes off Pinabel. Ganelon’s defender falls to the ground and raises no more. The judgement is complete. Ganelon is tied to four horses by the hands and by the feet and torn apart. The death of the traitor was horrible. But no death will return the Emperor’s nephew. Bitterly, Charlemagne mourns his beloved vassal.