The Red-Rising Trilogy

Mankind has conquered the entire solar system, completely terraforming all the smaller planets and larger moons of the gas giants. This expansion was made possible largely by genetic engineering, which is the central plot device in the trilogy. Mankind is divided into 14 casts, each genetically engineered for a specific hierarchical and practical role. At the top is gold, at the bottom is red. They include silver, innovators, financiers, and businessmen, blue, pilots, and astro-navigators bred to crew starships,. and obsidian, in monstrous race bred only for war.