But by far the greater number of the campaigns of Charlemagne were directed against the pagan Saxons, who almost alone of the German tribes still retained their ancient idolatry. Thirty years and more of his reign were occupied in these wars across the Rhine. Reduced to submission again and again, as often did the Saxons rise in desperate revolt. The heroic Witikind was the "second Arminius" (see p. 308) who encouraged his countrymen to resist to the last the intruders upon their soil. Finally, Charlemagne, angered beyond measure by the obstinacy of the barbarians, caused 4500 prisoners in his hands to be massacred in revenge for the contumacy of the nation. The Saxons at length yielded, and accepted Charlemagne as their sovereign, and Christianity as their religion. RESTORATION OF THE EMPIRE IN THE WEST (800).--An event of seemingly little real moment, yet, in its influence upon succeeding affairs, of the very greatest importance, now claims our attention. Pope Leo III. having called upon Charlemagne for aid against a hostile faction at Rome, the king soon appeared in person at the capital, and punished summarily the disturbers of the peace of the Church. The gratitude of Leo led him at this time to make a most signal return for the many services of the Frankish king. To understand his act a word of explanation is needed. For a considerable time a variety of circumstances had been fostering a growing feeling of enmity between the Italians and the emperors at Constantinople. Disputes had arisen between the churches of the East and those of the West, and the Byzantine rulers had endeavored to compel the Italian churches to introduce certain changes and reforms in their worship, which had aroused the most determined opposition of the Roman bishops, who denounced the Eastern emperors as schismatics and heretics. Furthermore, while persecuting the orthodox churches of the West, these unworthy emperors had allowed the Christian lands of the East to fall a prey to the Arabian infidels. Just at this time, moreover, by the crime of the Empress Irene, who had deposed her son Constantine VI., and put out his eyes, that she might have his place, the Byzantine throne was vacant, in the estimation of the Italians, who contended that the crown of the Cæsars could not be worn by a woman. Confessedly it was time that the Pope should exercise the power reposing in him as Head of the Church, and take away from the heretical and effeminate Greeks the Imperial crown, and bestow it upon some strong, orthodox, and worthy prince in the West.