9. While this long war was going on, the king also made an expedition into Spain, leaving garrisons behind to hold the Saxons in check. Crossing the Pyrenees with a large army he conquered all the cities and fortresses in the region and returned safely with his whole army, except for those that were slain by the treachery of the Basques. For when the army was coming back through the passes of the Pyrenees, strung out in a long line of march because of the narrowness of the defiles, the Basques made a sudden attack upon the rear-guard, which was protecting the wagons and baggage of the army. The place was well suited to an ambuscade, being thickly wooded and very steep; the Basques suddenly rushed down from the heights where they had been hiding and fell upon the rear-guard and destroyed it to the last man, seizing the baggage and escaping under cover of the approaching night.... In this attack were slain Eggihard, the king's seneschal, Anselm, count of the palace, and Hrotland, the warden of the marches of Brittany, along with many others. Up to the present time this attack has not been avenged, for the enemy dispersed so quickly that it was impossible to find them or to discover who were guilty.{45} 10. Karl also conquered the Bretons, a people dwelling in the remote western part of Gaul, along the shores of the ocean.... Then he again invaded Italy, this time marching through Rome to Capua, a city of Campania, and forcing the submission of Aragaisus, duke of Beneventum. 11. His next expedition was against Bavaria, which was soon reduced to subjection. This war was caused by the insubordination of duke Tassilo, whose wife, a daughter of Desiderius, urged him on to avenge the overthrow of her father. Tassilo made an alliance with the Huns, his neighbors, and prepared to attack the king. Karl, incensed at such presumption, immediately led an army in person to Bavaria, encamping on the river Lech, which separates Alamannia and Bavaria. Before invading the province he sent an embassy to the duke, who, seeing the hopelessness of attempting to oppose the king, immediately made his submission, offering hostages (among them his son Theodo) and swearing never again to revolt. Thus this war, which in the beginning threatened to be a serious affair, was brought to a rapid and successful conclusion.{46} But the king later summoned Tassilo to his presence and kept him a prisoner, not permitting him to return to his duchy; and from that time on the province was not ruled by a duke, but was divided into counties over which Karl placed counts of his own choosing.