The Saxons long resisted becoming Christians[43] and being incorporated into the orbit of the Frankish kingdom.[44] In 776 the Saxons promised to convert to Christianity and vow loyalty to the king, but, during Charlemagne's campaign in Hispania (778), the Saxons advanced to Deutz on the Rhine and plundered along the river. This was an oft-repeated pattern when Charlemagne was distracted by other matters.[44] They were conquered by Charlemagne in a long series of annual campaigns, the Saxon Wars (772–804).