The rise of the papacy since 1046 is almost linear. The popes throw off the chokehold of the roman aristocracy, they take over leadership of the church reform movement from the emperors, and by the end of the pontificate of Alexander II the Holy See has become universal with kings hailing the pope and not the emperor as their overlord.
In 1073 Hildebrand, the eminence grise of the last 20 years ascends the throne of St. Peter. His view of the role of the papacy goes even further than his predecessors. We know this because he laid it out in one of the most remarkable documents of the middle ages, the Dictatus Papae.
This ever expanding role of the papacy had to collide at some point with the other universal power, the emperor Henry IV. Letters are exchanged and words are spoken that set events in motion that will destroy them both.
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