The Pope is the name given to the current and past leaders of the Catholic church. The Popes were like kings unto themselves and were always cautious when talking to other rulers. The Pope is believed to be ordained by to rule as Gods voice on earth and thus his authority should be respected.   While the Roman empire stood the emperor was the spiritual and physical leader of the empire, but eventually the Roman Church became its own recognized nation with the pope recognized as its leader.  Eventually the Popes would look back on the documents from their predecessors and use it as proof that they had always been in charge.

Link to image: https://en.wikipedia.org/wiki/Pope

The medieval era was a particularly dark time as the Church ruled with a more Fire and brimstone approach then the clam and compassionate one, they have now.  The Church used the fear of going to hell to control the public and Encouraged babies to be baptized as soon as they are born so they can go to heaven as  without baptism they could be denied entry (which was cruel for them to say by the way).    They also heavily practiced the sacraments, spirituals rituals that were based of the miracles of Jesus.  It was believed that by preforming these rituals one could gain entry to heaven. Medieval Christan's also felt more inclined to commune with the saints as while they were still human, they were still holy, and they felt unworthy of communing directly with God. 

Link to image: https://malevus.com/dicastery/

The Germanic people ruled their subjects by laws centered around clanship. The Laws were made by the king who was the leader of the strongest clan, and that changed throughout the years.    The laws dictated that whenever a clan member was attacked or disrespected, they all were. Violence was often the best way to resolve the disputes between clans.  The Feud in Feudalism comes from these fights. Eventually The Germanics and Roman remnants became so intertwined you could not tell which from which. Eventually clan loyalty was forgotten and instead were replaced by Laws based of Romes.

Link to Image: https://en.wikipedia.org/wiki/Germanic_peoples

The Former Roman territory of Gaul became what is the current day heart of France. The Land was ruled by a powerful people called the Franks, and they were led by the Merovingians.   They were powerful and crafty and they eventual created a kingdom that would last for millennia to come, France.     The then king, Clovis went about consolidating power via way of the Romans, killing all rivals and family members and eventually defeated the last remnants of Rome and ensured Merovingian rule for the next two centuries.  Eventually the clan became weak and was overthrown by the Carolingians.

Link to Image: https://en.wikipedia.org/wiki/Franks