Charlemagne, the king of the Christian Franks, has been wreaking havoc in Muslim Spain for seven years and has conquered all the land except the city of Saragossa, still held by the Muslim king Marsilla. Marsilla, however, doubts that he can hold out long against the might of Charlemagne's army. Calling a council, he asks his wisest men what they ought to do to save themselves from being destroyed by the Franks. Blancandrin advises that they send Charlemagne an offer of vast riches and a promise that Marsilla will come to the Frankish capital of Aix to learn to be a good Christian and convert. The Saracens aren't planning on coming through on this offer, and in case the Franks suspect them of just such falsity, Blancandrin says that they can offer hostages to the Franks. Of course, once Charlemagne, back in France, realizes that neither Marsilla nor the treasure is on its way, the Franks will kill the hostages, but that's the cost of saving the city of Saragossa and Marsilla's honor. The pagans agree to the plan and Blancandrin goes as a messenger, olive branch in hand, to Charlemagne's camp.
The emperor and his men, having just taken the city of Cordova from the Muslims, are in a jolly mood when the messenger arrives. Blancandrin tells Charlemagne of Marsilla's offer and promises hostages, including his own son, as guarantees of good faith. Charlemagne is tempted by this proposed pact because of his weariness; after all, seven years is a long time to fight in a strange land, and the emperor is an old man. He calls together a council of his barons to meet under a pine.
Count Roland makes a fiery speech. He reminds the emperor that Marsilla has a history of deceit; once before Marsilla sent to the Franks a peace envoy delivering similar offers and promises, and Charlemagne sent over to the pagans two messengers, Basan and Basil, who the Saracens then slaughtered. Roland is uncompromising and fierce; he urges the Franks to lay siege to Saragossa and not to compromise with the treacherous Marsilla.
Ganelon, Roland's stepfather, calls such an extreme stance vainglorious and foolish; he's had enough of this hard campaign. Naimes agrees, arguing that the Franks have sufficiently humbled Marsilla and that the time has come for mercy. The council is swayed by Ganelon and Naimes; now a messenger must be chosen to go to Saragossa. Roland and Olivier volunteer, but Charlemagne insists that none of the twelve peers—his inner circle of vassals—may go.
Roland nominates Ganelon for the post; Ganelon's response is bitter rage. He threatens his stepson: "If God should deign that I come back again, then I shall stir up such a feud with you that it will last as long as you're alive!" (20.289-291). Ganelon rages, fearing that he may meet the same fate as Basan and Basil. Charlemagne responds by saying simply, "When I command, it's up to you to go" (23.318).
Charlemagne now bestows the staff and glove upon his messenger Ganelon, according to ceremony, but Ganelon, reaching out to take the glove, lets it drop. Seeing this, the Franks foresee that the embassy will have dire consequences for them. Ganelon leaves the council, with the staff, the letter, and Charlemagne's blessing.