In ancient Rome Governor

from creation of earliest roman subject provinces, governor appointed each year administer each of them. core function of roman governor magistrate or judge, , management of taxation , public spending in area .

under republic , empire, however, governor commanded military forces in province. republican governors men had served in senior magistracies (the consulate or praetorship) in rome in previous year, , carried related titles governor (proconsul or propraetor). first emperor, octavianus augustus (who acquired or settled number of new territories; officially style republican: princeps civitatis), divided provinces 2 categories; traditionally prestigious governorships remained before (in have become known senatorial provinces), while in range of others, retained formal governorship himself, delegating actual task of administration appointees (usually title legatus augusti). legatus appoint prefect (later procurator), man of equestrian rank, act deputy in subregion of larger province: infamous character of pontius pilate in christian gospels governor of sort.

a special case egypt, rich private domain , vital granary, emperor inherited theocratic status of pharaoh. emperor represented there governor sui generis styled praefectus augustalis, title evoking religious cult of emperor.

emperors diocletian (see tetrarchy) , constantine in third , fourth centuries ad carried out root , branch reorganisation of administration 2 main features:

provinces divided , became more numerous (italy itself, before colonizing homeland , brought system first time); grouped dioceses, , dioceses in turn 4 praetorian prefectures (originally each under residing co-emperor);
military responsibilities removed governors , given new officials called comes rei militaris (the comital title granted many court , civilian administrative positions) or dux, later magister militum.

the prestigious governorships of africa , asia remained title proconsul, , special right refer matters directly emperor; praefectus augustalis in alexandria , comes orientis in antioch retained special titles. otherwise, governors of provinces had various titles, known consularis, correctorwhile others praeses. apart egypt , east (oriens – viz greater syria), each diocese directed governor known vicarius. prefectures directed praefecti praetorio (greatly transformed in functions role in empire).