The Sixth Fleet was one of the nine main interstellar battlegroups which made up the navy of the Galactic Federation of Free Alliances government during the Second Galactic Civil War in 40 ABY. It represented the first expansion of the Galactic Alliance naval structure beyond the five battlegroups which had comprised the main force of the Fleet under the former New Republic, and probably still in the early years of the new government. Well before the end of 40 ABY, however, it had been joined by the Seventh, Eighth and Ninth Fleets.