The correct chronological order is as follows:
Fall of the Western Roman Empire.
The Western Roman Empire fell in in 476 AD.
Gregory I becomes pope.
Gregory I becomes pope in 590 AD.
Height of the medieval period.
The medieval period peaked around 1000 - 1300 AD, or 1150 AD if you take the mean.
Fall of the Eastern Roman Empire.
The Eastern Roman Empire, or the Byzantine Empire, fell at 1453.
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Learn more about the Roman Empire (West & East):
https://brainly.com/question/11415671?referrer=searchResults - The different churches followed by the respective halves of the empire.
https://brainly.com/question/20369245?referrer=searchResults - The result of moving the capitol to Byzantine, away from Rome.
