In 975, shortly after Nicephorus Phocas' campaign, the strategos commanding Crete was ranked 23rd out of 83 strategoi in the Byzantine administrative hierarchy, a fact illustrative of the relative significance accorded to the theme of Crete. Several names of strategoi have survived, such as those of Eumathios and Philaretos Vracheon, who witnessed the will of St. John Xenos on 20th September 1027.
From the late 11th or early 12th century onwards, the commander of Crete bore the title of Duke or Katepano rather than strategos, as a result of administrative reforms promulgated by Emperor Alexius I Comnenus. In addition to being political administrators, the dukes had wide-ranging jurisdiction over economic and judicial matters and were at the head of the local military.
In common with other themes, on an internal level the island was subdivided into smaller administrative regions. Three of these so-called tourmes are know to us: Kalamon, "North of Mesarea" and Knossos.