Who was Justinian’s contemporary in Western Europe? What are the similarities and differences between the tasks

Who was Justinian’s contemporary in Western Europe? What are the similarities and differences between the tasks that were solved by the emperors of Byzantium and the kings in Europe at that time?

It is mainly about the 6th century AD, Justinian lived from 483 to 565. The similarity of tasks consisted in confronting barbarians and creating codes of laws, organizing taxation. The difference was as follows: in Western Europe, states were created by barbarian peoples on the territory of the former Western Roman Empire, and Byzantium continued the traditions of statehood, albeit with a number of changes. For example, in 529, Justinian closed the Platonic Academy.
In France, his contemporary was Clovis in the kingdom of the Franks and his son Theodoric. And also Theodebert, Alaric II (kingdom of the Visigoths). King Arthur is one of the legendary characters of his contemporaries.