Umbara was a shadowy planet within the reaches of the Ghost Nebula. It was home to the Umbarans, a race of pale near-Humans. It was part of the Galactic Republic from that government's earliest days. Sith Academy
Muzara was a planet in the Expansion Region. Humans from Brentaal colonized the planet 4,000 BBY, barely avoiding conflict with the native Muzaran people, who were also known as the Muza.
