Theme of Hellas

Theme of Hellas Ἑλλάς, Ἑλλάδα, θέμα Ἑλλάδος
Theme of the Byzantine Empire
687/695 – 12th century
Map of Byzantine Greece c. 900, with the themes and major settlements.
Historical era		Middle Ages
•	Established	687/695
•	Dissolution into smaller districts.	12th century
Today part of		Greece

The Theme of Hellas (Greek: θέμα Ἑλλάδος) was a Byzantine military-civilian province (thema, theme) located in southern Greece. The theme encompassed parts of Central Greece, Thessaly and, until c. 800, the Peloponnese. It was established in the late 7th century, and survived until the late 11th/12th century.

"Hellas" was already in use in the 6th century to designate southern Greece in an administrative context, being employed in the Synekdemos as an alternative name for the Roman province of Achaea. During the late 6th and early 7th centuries, the final collapse of the Danube frontier allowed large-scale Slavic invasions and settlements to occur all over the Balkan peninsula. From 578, Slavic raids reached Thessaly and southern Greece. Aided by the Byzantine Empire's preoccupation with the long and bloody wars with Sassanid Persia in the east, and with the Avar Khaganate in the north, the Slavs raided and settled almost at will. The Slavic settlement that followed the raids in the late 6th and early 7th centuries affected the Peloponnese in the south and Macedonia in the north far more than Thessaly or Central Greece, with the fortified towns largely remaining in the hands of the native Greek population. Nevertheless, in the first decades of the 7th century the Slavs were free to raid Thessaly and the south relatively unhindered; according to the Miracles of Saint Demetrius, in ca. 615 the Slavic tribes even built monoxyla and raided the coasts of Thessaly and many Aegean islands, depopulating many of them. Some of the native Greek population fled to the fortified cities, to off-shore islands, or to Italy.

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