On arrival at an island, Theodore would often be carrying a letter of introduction to the local demarch or eparch, or he would try to find either dignitary, with the hope of securing decent lodgings and assistance during his stay. The demarch and the eparch were the most prominent citizens in the communities visited by Theodore.
A demarch, or demarchos, is roughly the equivalent of a mayor in Greek local government, The area controlled by the demarch is referred to as the demarchy and, at the time of Theodore’s travels, could be as small an area as a single village. Nowadays, it is more likely to be a much larger area such as a geographic region, an island or group of islands. The building from which the demarch conducts his official business is the demarcheion. The word demarchos is derived from the Greek words demos (the people) and archon (lord or ruler).
An eparch, or eparchos, is equivalent to a bishop who is in control of an eparchy (eparchia in Greek), or diocese.