During the eighth-century the Carolingian Franks sought to stamp out Germanic paganism, when for instance, Charlemagne destroyed the mighty tree trunk Irminsul that supported the heavenly vault of pagan Saxons in much the same way that Boniface had destroyed Thor's Oak before. Charlemagne then instituted a forced mass-baptism, which was never forgiven and incited the Saxons to revolt whenever Frankish forces were far away; the Saxons—under the leadership of Widukind—even wiped-out Christian mission centres in Frankish territory. Historian J.M. Wallace-Hadrill asserts that Charlemagne was "in deadly earnest" about extirpating paganism and that his "kingly task" included converting the heathen pagans "by fire and sword if necessary." Germanic paganism's lasting power and influence is revealed to some degree by the amount of anti-pagan measures undertaken during the period of Frankish ascendancy.