The Expanse was the name given to the ore-rich section of the Tapani Sector under the control of the Tapani Federation during the Rebellion Era. The area was the remnant of a small stellar empire which occupied the sector centuries before. Six of the seven major noble houses in the sector were located in the Expanse, with House Cadriaan being the only noble house not in the Expanse. The Freeworlds Territory's border was dictated by the edge of the expanse.