The first irruption of the Saracens occurred in 713. Ever since Spain had become Moorish, the Mahommedans had been scouring the Mediterranean, robbing and plundering in all the islands, and founding in many places a dominion of protracted duration. The Greek Emperors, whose hands were full in the East, totally abandoned the West, which found new protectors in the Franks. That Charlemagne had to do with Corsica or with the Moors there, appears from his historian Eginhard, who states that the Emperor sent out a fleet under Count Burkhard, to defend Corsica against the Saracens. His son Charles gave them a defeat at Mariana. These struggles with the Moors are still largely preserved in the traditions of the Corsican people. The Roman noble, Hugo Colonna, a rebel against Pope Stephen IV., who sent him to Corsica with a view to rid himself of him and his two associates, Guido Savelli and Amondo Nasica, figures prominently in the Moorish wars. Colonna's first achievement was the taking of Aleria, after a triple combat of a romantic character, between three chivalrous paladins and as many Moorish knights. He then defeated the Moorish prince Nugalon, near Mariana, and forced all the heathenish people in the island to submit to the rite of baptism. The comrade of this Hugo Colonna was, according to the Corsican chronicler, a nephew of Ganelon of Mayence, also named Ganelon, who had come to Corsica to wipe off the disgrace of his house in Moorish blood. The Tuscan margrave, Bonifacius, after a great naval victory over the Saracens on the coast of Africa, near Utica, is now said to have landed at the southern extremity of Corsica on his return home, and to have built a fortress on the chalk cliffs there, which received from its founder the name of Bonifazio. This took place in the year 833. Louis the Pious granted him the feudal lordship of Corsica. Etruria thus acquires supremacy over the neighbouring island a second time, and it is certain that the Tuscan margraves continued to govern Corsica till the death of Lambert, the last of their line, in 951. Berengarius, and after him Adalbert of Friuli, were the next masters of the island; then the Emperor Otto II. gave it to his adherent, the Margrave Hugo of Toscana. No further historical details can be arrived at with any degree of precision till the period when the city of Pisa obtained supremacy in Corsica.