| Theme of Sicily|
Σικελία, θέμα Σικελίας
|Theme of the Byzantine Empire|
|Capital||Syracuse, then Rhegion|
|Historical era||Middle Ages|
|•||Fall of Taormina to the Arabs||902|
|•||Theme renamed to Calabria||Mid-10th century|
|Today part of|| Italy|
The Theme of Sicily (Greek: θέμα Σικελίας - Thema Sikelias) was a Byzantine military-civilian province (thema, theme) existing from the late 7th to the 10th century, encompassing the island of Sicily and the region of Calabria in the Italian mainland. Following the Muslim conquest of Sicily, from 902 the theme was limited to Calabria, but retained its original name until the middle of the 10th century.
Ever since its reconquest from the Ostrogoths by Belisarius in 535–536, Sicily had formed a distinct province under a praetor, while the army was placed under a dux. A strategos (military governor) is attested on the island in Arab sources between 687 and 695, and it is at that time that the island was probably made into a theme.
The theme was based in Syracuse, traditionally the chief city of Sicily. It comprised not only the island, which was divided into districts called tourmai, but also the mainland duchy of Calabria (Greek: δουκᾶτον Καλαυρίας, doukaton Kalavrias), which extended roughly up to the river Crati. In addition, the strategos of Sicily exercised some authority—varying according to the prevailing local political faction—over the autonomous duchies of Naples, Gaeta and Amalfi.
The Muslim conquest of the island began in 826. Following the fall of Syracuse in 878 and the conquest of Taormina in 902, the strategos moved to Rhegion, the capital of Calabria. During the first half of the 10th century, the Byzantines launched a number of failed expeditions to regain the island and maintained a few isolated strongholds near Messina until 965, when Rometta, the last Byzantine outpost, fell. The post of "strategos of Sicily" was thus retained as the official title until the mid-10th century, when the "strategos of Calabria" begins to appear in the lists.
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