Roman Greece

Militarily Greece itself declined to the point that the Romans conquered the land (168 BC onwards), though Greek culture would in turn conquer Roman life. Although the period of Roman rule in Greece is conventionally dated as starting from the sacking of Corinth by the Roman Lucius Mummius in 146 BC, Macedonia had already come under Roman control with the defeat of its king, Perseus, by the Roman Aemilius Paullus at Pydna in 168 BC. The Romans divided the region into four smaller republics, and in 146 BC Macedonia officially became a province, with its capital at Thessalonica. The rest of the Greek city-states gradually and eventually paid homage to Rome ending their de jure autonomy as well. The Romans left local administration to the Greeks without making any attempt to abolish traditional political patterns. The agora in Athens continued to be the centre of civic and political life.
Caracalla's decree in 212 AD, the Constitutio Antoniniana, extended citizenship outside of Italy to all free adult males in the entire Roman Empire, effectively raising provincial populations to equal status with the city of Rome itself. The importance of this decree is historical rather than political. It set the basis for integration where the economic and judicial mechanisms of the state could be applied throughout the Mediterranean as was once done from Latium into all of Italy. In practice of course, integration did not take place uniformly. Societies already integrated with Rome, such as Greece, were favored by this decree, in comparison with those far away, too poor or just too alien such as Britain, Palestine or Egypt.
Caracalla's decree did not set in motion the processes that led to the transfer of power from Italy and the West to Greece and the East, but rather accelerated them, setting the foundations for the rise of Greece as a major power in Europe and the Mediterranean in the Middle Ages.