Board Thread:General Discussion/@comment-26203045-20150314090036/@comment-28584561-20150314092228

Not only Pearl, as A man of questionable sanity has stated all the Crystal Gems were once part of the homeworld faction, that means that Rose, Pearl, Ruby, and Sapphire came here to earth with the original plan of conquering it. But Rose saw it as wrong and rebelled, bringing Pearl, Sapphire, and Ruby with her, and they also recruited Amethyst along the way.