A pope is in need of help from the Frankish king. After being physically attacked by his enemies in the streets of Rome. It is not known what is agreed, but Charlemagne travels to Rome in 800 to support the pope. But unexpectedly as Charlemagne rises from prayer, the pope places a crown on his head and acclaims him emperor. Charlemagne expresses displeasure but accepts the honor. The displeasure is probably diplomatic, for the legal emperor is undoubtedly the one in Constantinople. Nevertheless this public alliance between the pope and the ruler of a confederation of Germanic tribes now reflects the reality of political power in the west. And it launches the concept of the new Holy Roman Empire that will play an important role throughout the middle ages. The Holy Roman Empire only becomes formally established in the next century. But it is implicit in the title adopted by Charlemagne in 800: 'Charles, most serene Augustus, crowned by God, great and pacific emperor, governing the Roman Empire.'
In 962 a pope once again needs help against his Italian enemies. Again he appeals to a