The Theme of the Peloponnese (Greek: θέμα Πελοποννήσου) was a Byzantine military-civilian province (thema, theme) encompassing the Peloponnese peninsula in southern Greece. It was established in c. 800, and its capital was Corinth.
The Peloponnese, or at least the areas controlled by the Byzantine Empire, formed part of the theme of Hellas from the late 7th century on. In about 800, however, Hellas was split up, and while the name was retained for the territory comprising eastern Central Greece and Thessaly, the Peloponnese became a separate theme. The first known strategos (general placed in charge of each theme) of the Peloponnese is Leo Skleros, attested for 811 (or perhaps 805 as well), who may even be the first holder of the office. The formation of the new province is directly linked to the re-imposition of the Byzantine government's control over the Slavic tribes that had settled in much of Greece, as well as to the region's resettlement with Greeks from Italy and Asia Minor.
The strategos of the Peloponnese ranked first in the hierarchy of the "western" (i.e. European) thematic governors. The role of his administration was mostly controlling the Slavic tribes of the interior and defence against the Arab raids, frequent in the 9th and 10th centuries: among other subordinate officials, a tourmarches was charged with the defence of the coast and even had a naval squadron of four chelandia under his orders. After the Byzantine reconquest of Crete in 961 put an end to the piratical emirate there, the Peloponnese prospered greatly. From the late 10th century on, the thematic administration was often combined with that of Hellas, and in the late 11th century, this union became permanent, with both provinces coming under the control of the megas doux, the commander-in-chief of the Byzantine navy. Due to the latter's absence from the province, however, the local administration remained under the local praetor, a position often held by senior and distinguished officials like the legal scholars Alexios Aristenos and Nicholas Hagiotheodorites. The joint theme of Hellas-Peloponnese was subdivided further during the 12th century into a series of smaller districts variously termed oria, chartoularata and episkepseis.a[›] The Peloponnese remained under Byzantine control until the early 13th century (1205), when, in the aftermath of the Fourth Crusade, the Latin Principality of Achaea was established there.
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^ a: The episkepseis were large domains allocated for the support of individuals, noble houses or churches and monasteries. The oria were districts tasked with the maintenance of warships and crews for the navy. The chartoularata were districts placed under a chartoularios, and tasked with provisioning the imperial army with horses and pack animals. They also seem to have functioned as military assembly points, similar to the old metata and aplekta.
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