Sector

A Sector was a division of galactic territory used by the Galactic Republic and its successor state, the Galactic Empire, for the purposes of political, economic and military organization.

Under Republic terminology, a Sector was defined as having a maximum of fifty inhabited star systems. Many sectors grew larger than intended, however, due to the rapid galactic expansion and colonization beginning around 5,000 BBY.

Under the Empire, Palpatine replaced senators with Moffs as Sectorial governors. Many Sectors were rearranged, expanded, or collapsed all together as Palpatine saw fit. Years later, at the recommendations of Wilhuff Tarkin, Sectors were further clumped together in Oversectors, ruled by a Grand Moff.

Many Sectors owed their name to their primary system which in turn was named after its primary planet. For example, the planet Selene belonged to the Selene system, and thus, to the Selene Sector.