Catholicism spread west - Orthodox Christian spread east - Latin was the court language - Greek was the official language - Civilian bureaucracy
Historical map of Europe in the year 800 AD
This is a map of the Barbarian Kingdoms. Justinian claimed the Vandal kingdom his, along with the the Iberian coast (part of the Visigoth kingdom),the Italian peninsula from the Ostrogoths. This resulted in him having most of the Mediterranean coastline.