But the Frenchmen's truculent attitude forbids the guards' approach, and thus gives the ambassadors a chance to inform Marsile that Ganelon has promised to help them to outwit Charlemagne by depriving him of his most efficient general.

Hearing this, Marsile's anger is disarmed; and he not only agrees to their plan to surprise Roland while crossing the Pyrenees, but sends Ganelon back laden with gifts.
On rejoining his master at the foot of the mountains, Ganelon delivers the keys of Saragossa, and reports that the caliph has sailed for the East, with one hundred thousand men, none of whom care to dwell in a Christian land.

Hearing this, Charlemagne, imagining his task finished, returns thanks to God, and prepares to wend his way back to France, where he expects Marsile to follow him and do homage for Spain.
Karl the Great hath wasted Spain, Her cities sacked, her castles ta'en; But now "My wars are done," he cried, "And home to gentle France we ride." _The Rear-guard and Roland Condemned to Death._ On the eve of his return to "sweet France," Charlemagne's rest is disturbed by horrible dreams, in one of which Ganelon breaks his lance, while in the other wild animals are about to attack him.

On awaking from this nightmare, Charlemagne divides his army so as to thread his way safely through the narrow passes of the mountains, arranging that a force shall remain twenty miles in his rear to make sure he shall not be surprised by the foe.

When he inquires to whom this important command shall be entrusted, Ganelon eagerly suggests that, as Roland is the most valiant of the peers, the task be allotted to him.