Charlemagne's troops, returning from the siege of Saragossa, suffered in the Pyrenean pass of Roncesvalles attack Basque tribes helped by Muslims. The narrowness of the step and the weight of the arms of the Carolingian army favored the success of the ambush on the rear of the Franks.
In this tragic episode died Roldan, but the legend made him go down in the annals of literature (Chanson de Roland, Rolandstat, Orlando Furioso, etc.) as the champion, who with his magic sword "Durendal" gift of his lord Charlemagne , and the horn "Oliphant" 100,000 Saracens faced. A sword blow opened a passage between the Pyrenean mountains which still is called "Brèche de Roland".