The One Piece wiki currently lists Figarland Garling as a former champion of God Valley instead of king or ruler. I tried reading three of the translations but none of them say champion.
I am wondering whether God Valley could have been hosting a type of underground arena battle for powerful people. Figarland Garling may have been the champion of all of the fighters. You could imagine that slaves and random collected people around the world might be gathered to battle each other in this arena to add to the ranks of the World Government or the Navy. Maybe that’s how the God’s Knights were created in the first place, or maybe the God’s Knights were a test for other champions who won.
We saw in chapter 1074 that when Kuma was a child he was kept in some location that is either unfamiliar to us or is just undisclosed as of yet. People have already speculated that he was at God Valley in that scene, and if that is true I think when he says “if I go back, I’ll die anyway,” he could have been referring to fighting in the arena. Kuma could also have just won in a battle but knows that he could die if he still fights. If this is true the God Valley could be where he ate his devil fruit as well as where he got the title of Tyrant. This would all mean that Kuma did in fact win or at least escape God Valley.
It would make sense that Rocks would attempt to destroy God Valley (or bring it to light) because of the amount of powerful people that are either celestial dragons or those that work for them who reside there. We know Kaido ate his fruit at God Valley when Big Mom gave it to him, and this fits in with my theory because as an arena the celestial dragons could have been holding a lot of powerful fruits to give to champions. We may see that a lot of the god’s knights have powerful devil fruits which connect back to God Valley.
Finally, this scenario would mean that we could see a God Valley flashback from the perspective of Kuma as a slave, and we might learn about why Kuma as well as his fruit are so special.
Does this sound like it could happen? In my opinion it fits well enough into the story of One Piece and wouldn’t necessarily be out of place as a plot point. If I did my due diligence, it also doesn’t break anything lore-wise.
*Theory by basi_CF_unction