Cerea was ruled by hippies who limited technology on the planet in order to preserve its environment. A few designated areas allowed technology, but the rest of the planet had a strict anti-technology policy. Cerea was pretty isolated, and refused to join the Republic because they didn't want their planet getting all dirty. The planet remained neutral during the Clone Wars, which was something neither side could tolerate. Approximately 1,000,000 Cereans were killed while the two sides fought over the planet and the delicious cereal they assumed was inside.