The 26 Draconis system us a planetary system that is controled by the United Nations Space Command. This system was one of the first to harber Insurrects. On march 2, 2494, Insurrents hijacked the UNSC Callisto and killed the crew (This event is belived to be the start of the undeclared civil war between Hummanity).
Planets:
Sources
Halo: Evolutions - Essential Tales of the Halo Universe - The Impossible Life and the Possible Death