In 772, Charlemagne, ruler of the Franks, started the Saxon Wars to conquer the lands of the North German Plain. According to the "Royal Frankish Annals", the Westphalian noble Widukind refused to appear at the 777 Imperial Diet in Paderborn and fled across the Elbe to Nordalbingia (or possibly further to the court of the Danish king Sigfred). Even after Widukind's submission and Christianization in 785, the Nordalbingian tribes remained reluctant until they were finally defeated at the 798 Battle of Bornhöved by the combined forces of the Franks and their Obotrite allies led by Prince Drożko. The Saxons lost 4,000 people, 10,000 families of Saxons were deported to other areas of the Carolingian Empire.