 The influential American conservative political scientist, adviser and academic Samuel P. Huntington argued that this cultural division still existed during the Cold War as the approximate Western boundary of those countries that were allied with the Soviet Union.In AD 800 under Charlemagne, the Early Medieval Franks established an empire that was recognized by the Pope in Rome as the Holy Roman Empire (Latin Christian revival of the ancient Roman Empire, under perpetual Germanic rule from AD 962) inheriting ancient Roman Empire's prestige but offending the Roman Emperor in Constantinople.The crowning of the Emperor by the Pope led to the assumption that the highest power was the papal hierarchy, quintessential Roman Empire's spiritual heritage authority, establishing then, until the Protestant Reformation, the civilization of Western Christendom.