Sort of. One of the spirits of the dead Ootsutsuki Clan showed Hinata a vision of the past, where the Ootsutsuki Clan waged a civil war over their interpretation of "Homura's celestial decree." The branch family believed that Homura ordered them to observe mankind for a thousand years, and if after all that time they determined that the shinobi of the Earth had betrayed Hagoromo's ideals and were using chakra for evil, they would then destroy them all. What the main family believed the decree to be is never actually explained, but it doesn't matter because the branch family won the civil war.
That explanation doesn't really cut it though, because the flashback shows the branch family using the Tenseigan to absolutely slaughter the main family while suffering no casualties of their own. What happened to all of the hundreds/thousands of victorious branch family Ootsutsuki besides Toneri is never explained. Toneri mentions at one point that his father died when he was young, but he neglects to mention how he died.
Also the dead spirit refers to Hinata as the "Byakugan Princess", but what this means is also never really explained beyond the fact that it apparently means she somehow has Homura's chakra and can thus pass through the barrier placed on the Tenseigan that prevents non-Ootsutsuki from touching it, which is how she was able to help Naruto destroy it.