The extinct Shola species were a unique race originally native to Shola. They presumably had a rather advanced society, in that the planet had mines and tunnels extending nearly to the core itself. However, they were wiped out along with their cities, when the planet was ravaged. It was theorized that it was their own doings that caused the scarring of their planet. These people left behind ruins.
Sources
- Star Wars: Empire at War (Mentioned only)