h some areas such as the southeastern Peloponnese remaining pagan until well into the 10th century AD.
The Roman Empire in the east, following the fall of the Empire in the west in the 5th century, is known to history as the Byzantine Empire and lasted until 1453. With its capital in Constantinople, its language and literary culture was Greek and its religion was predominantly Eastern Orthodox. From the 4th century, the Empire's Balkan territories, including Greece, suffered from the dislocation of the Barbarian Invasions. The raids and devastation of the Goths and Huns in the 4th and 5th centuries and the Slavic invasion of Greece in the 7th century resulted in a dramatic collapse in imperial authority in the Greek peninsula. Following the Slavic invasion, the imperial government retained control of only the islands and coastal areas, particularly cities such as Athens, Corinth and Thessalonica, while some mountainous areas in the interior held out on their own and continued to recognize imperial authority. Outside of these areas, a limited amount of Slavic settlement is generally thought to have occurred, although on a much smaller scale than previously thought.
The Byzantine recovery of lost provinces began toward the end of the 8th century and most of the Greek peninsula came under imperial control again, in stages, during the 9th century. This process was facilitated by a large influx of Greeks from Sicily and Asia Minor to the Greek peninsula, while at the same time many Slavs were captured and re-settled in Asia Minor and those that remained were assimilated. During the 11th and 12th centuries the return of stability resulted in the Greek peninsula benefiting from strong economic growth – much stronger than that of the Anatolian territories of the Empire. Following the Fourth Crusade and the fall of Constantinople to the “Latins” in 1204 most of Greece quickly came under Frankish rule (initiating the