Of all of Charlemagne’s military campaigns, the one which most caught the imagination of bards and minstrels was his expedition against the Moors in Spain. Charlemagne inherited an enmity towards the Spanish Moslems from the Merovingian rulers. His grandfather had defeated them at Poitiers in 732, but the Spanish frontier continued to remain insecure.
At the general assembly at Paderborn in 777, a contingent of Arab leaders, hostile to the ruling emir of Cordova, urged Charlemagne to mount an attack against Spain, promising to recognize him as their ruler if he were successful. Charlemagne negotiated with them in the presence of the subjugated Saxon leaders in order to impress them with his worldliness and ended by promising to conquer Spain.
However, Charlemagne’s Spanish campaign was to achieve only a partial success. After gathering an army in Aquitaine in the spring of 778, he divided his forces into two expeditionary units. One headed for Barcelona and the other, led by Charlemagne himself, crossed the Pyrenees and attacked Pamplona. Charlemagne’s forces win control of the city.
Meanwhile, the Moslem rebels under Soliman ben Alarabi wrested the city of Saragossa from the emir of Cordova, and it appeared as if a combined force of Frankish and Moslem troops might defeat the government of the emir.
Charlemagne proceeded to Saragossa, meeting on the way with his Barcelona contingent. The march to Saragossa was uneventful, then, seemingly out of nowhere, squadrons of Arab cavalry appeared riding towards him in battle dress. The Franks had no time to organize them easily, and Charlemagne’s defeat was as bitter as it must have appeared inexplicable.
What had happened was that Soliman had been overconfident, and a man loyal to the emir had taken over his army. Thus the Moslem force which Charlemagne considered an ally had turned to attack him and had dealt him an unexpected defeat.