[The unsuccessful expedition against the Moors in Spain took place at this time, and the absence of Frankish armies on the northern frontier induced the Saxons to rebel again.] They destroyed the newly built churches, the priests were slain, the Franks were driven out and the Frankish territory itself was attacked. Charles at once sent a force of Franks and Alamanni against the Saxons, and in the years 779 and 780 the king himself marched with a mighty army into the seditious land. All the districts submitted anew and promised allegiance and the acceptance of Christianity. But, taught by sad experience, Charles did not trust their promises again and planned means to enforce obedience. Numerous fortresses were built about the country, especially on the Frankish boundary and along the Elbe; strong garrisons in these strongholds confined the Saxons from east and west and really maintained peace for some time. Charles made use of this period to carry out measures designed to break up forever the old heathen cult and the hereditary national freedom. The Frankish military and judicial system was now introduced here, as it had previously been in the Lombard kingdom; the land was divided into counties, the government of which was placed in the hands of Frankish lords or of Saxon nobles who had submitted to Charles. The division of the land into bishoprics was also begun. Christian priests were settled in the country, and the people, when they did not voluntarily accept the teachings of Christ, were forced to baptism, to ecclesiastical life, and the ordering of tithes. In the year 782 the king held a great and brilliant diet at the sources of the Lippe; his rule in Saxony appeared to be as unhampered as in his own house. He was already laying plans to extend his own kingdom beyond Saxony to the east among the Slavic races. It was on an expedition against the Sorbs, who dwelt between the Saale and the Elbe, that the Saxons had for the first time to render the king military service. Apparently the king desired to give the warlike spirit of this people an occupation in a different direction.
The new regulations of Charles cut deep into the very life of the people. The ancient Germanic freedom bled from mortal wounds. Too exhausted to maintain itself longer upright, it nevertheless still possessed sufficient energy to fight convulsively against destruction. Witikind now reappeared among the Saxons and summoned his people to the defence of their ancient faith and hereditary right. All Saxony flew to arms; even the Frisians joined Witikind. A great common determination inspired these last champions of ancient Germanic liberty. Hardly had Charles gone forth when the whole country was in revolt. The priests were slain, the nobles who had submitted to the Franks were exiled, and preparations were made for a life and death struggle. The army sent against the Sorbs had to turn about and march immediately against Witikind and his hordes, but in the Süntel hills near the Weser it suffered a complete defeat, and reinforcements sent forward from the Rhine had difficulty in saving the scanty remnants.
Charles himself, however, was already on the march with a new army, and again resistance seemed to be paralysed upon his appearance in person. Witikind gave up Saxon liberty for lost and fled again to the Danes. As a stern avenger and judge, Charles now called the faithless people to account. He demanded the surrender of the guilty; 4,500 Saxons were delivered into his hands, and he had them all beheaded in one day at Verden, thinking that, in this desperate struggle, liberty, if cut down by one mighty blow, would bleed to death at once.