Military units and formations established in the 6th century

The Optimatoi (, from , "the Best Men") were initially formed as an elite Byzantine military unit. In the mid-8th century, however, they were downgraded to a supply and logistics corps and assigned a province (thema) in north-western Asia Minor, which was named after them. As an administrative unit, the 'Theme of the Optimatoi''' (, thema Optimatōn'') survived until the Ottoman conquest in the first decades of the 14th century.