The Kilian system is the largest planetary system in the United Empire of Earth (UEE). Discovered in 2463, it was a key stepping stone in Humanity’s early push outward from the Sol system. Four of its fourteen planets are populated. Kilian became the main headquarters for the Human military in 2631. MacArthur (Kilian V) is the base of operations for the UEE Navy, while Corin (Kilian IX) is the home base of the UEE Marines. Keene (Kilian VII) is the system's only populated world with Senatorial representation.