At the time Karl der Grosse was crowned as Kaiser des Heilig Römischen Reichs (800AC), he was King of the Franks. His territorium comprised what today is France Germany Austria Belgium Netherlands. [...]

Eduardo Puricelli

Geschichte

[...] At what stage did France separate from the above and became Frankenreich and separately Heilig Römischer Reich i.e. two rulers.?????

In 799, for the third time in half a century, a pope is in need of help from the Frankish king. After being physically attacked by his enemies in the streets of Rome (their stated intention is to blind him and cut out his tongue, to make him incapable of office), Leo III makes his way through the Alps to visit Charlemagne at Paderborn.
It is not known what is agreed, but Charlemagne travels to Rome in 800 to support the pope. In a ceremony in St Peter's, on Christmas Day, Leo is due to anoint Charlemagne's son as his heir. But unexpectedly (it is maintained), as Charlemagne rises from prayer, the pope places a crown on his head and acclaims him emperor.

Charlemagne expresses displeasure but accepts the honour.

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 which 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.'

The imperial role accorded by the pope to Charlemagne in 800 is handed on in increasingly desultory fashion during the 9th century. From 924 it falls into abeyance. But in 962 a pope once again needs help against his Italian enemies. Again he appeals to a strong German ruler.
The coronation of Otto I by pope John XII in 962 marks a revival of the concept of a Christian emperor in the west. It is also the beginning of an unbroken line of Holy Roman emperors lasting for more than eight centuries. Otto I does not call himself Roman emperor, but his son Otto II uses the title - as a clear statement of western and papal independence from the other Christian emperor in Constantinople.

Otto and his son and grandson (Otto II and Otto III) regard the imperial crown as a mandate to control the papacy. They dismiss popes at their will and instal replacements more to their liking (sometimes even changing their mind and repeating the process). This power, together with territories covering much of central Europe, gives the German empire and the imperial title great prestige in the late 10th century. But subservience was not the papal intention in reinstating the Holy Roman Empire. A clash is inevitable.
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