Board Thread:Episode Discussions/@comment-25319479-20160630125952/@comment-26369387-20160702210239

^ The Fourth Databook says pretty clearly that Kaguya came to Shinobi Earth with Ōtsutsuki clan, her being the leader, and after sealing of Ten-Tails, Hamura went to newly created Moon with said clan to guard Demonic Statue, minus the descendents of Hamura that would later become Hyūga clan. Also, Hamura is the one who inherited Byakugan, not Hagoromo.