Board Thread:News and Announcements/@comment-27628871-20151218220901/@comment-27150321-20151227205927

It's likely that post-Gem War Gems are told very little about the Gem Wars as Homeworld was virtually defeated by the Crystal Gems, so it's a black mark in Homeworld history, something that would be downplayed or kept from Homeworld civilians in case it inspired another rebellion on a Gem colony or even Homeworld. During The Return it is mentioned that Homeworld managed to counterattack and took out the majority of the CG (personally I think that they are responsible for Gems on Earth being corrupted) although they assumed that they wiped out all of the CG. Hence why Peridot went to Earth not knowing about the CG, her mission was to check on the Cluster and there was no expected resistance to be found on Earth so she was not told about them. It is after Pearl gives away who was repelling Peridot's attempts to complete her mission that Peridot finally accessed records to see who the CG are, although we must bear in mind she also had Lapis Lazuli giving her information about the CG later.