or Battle of Roncevaux
(August 15, 778) Basque attack on Charlemagne 's army at a pass in the Pyrenees in northern Spain.
It occurred when Charlemagne was returning to Aquitaine after a campaign against the Muslims in Spain, and his rear guard was ambushed and massacred by Basque soldiers. The battle is treated in the 11th-century Chanson de Roland , in which the attackers are Moors and the rear guard is led by Charlemagne's nephew Roland.