Medieval Europe I 900 CE
The Carolingian empire has fragmented into several kingdoms.
The Roman empire is at its full extent, peaceful and prosperous, but threats are growing beyond its frontiers.
A hundred years' later, all the western provinces have been lost to the Roman Empire; only the Eastern half remains.
The Roman empire under Justinian has recovered some western territories.
The Eastern Roman Empire has suffered great territorial loss.
The Eastern Roman Empire (or Byzantine Empire) has suffered further massive loss of territory, this time to the Muslim Arabs.
The Frankish ruler Charlemagne has conquered a large part of Europe, and thus founded the Carolingian empire.
The king of the Germans has revived the title of emperor, and thus founds the Holy Roman Empire.
Much of central and eastern Europe has been incorporated into the family of Christian kingdoms - "Christendom".