In all these caves in Zion (plus some other places) there are diaries left on computers, plus remains of dead people and their stuff that as far as I can understand reference to the "first" people to inhabit Zion.
There are the 100 Vault 22 inhabitants, some survivalist hopeless guy who gets kids anyway plus the ranger.
I am assuming that they all moved in approximatelty at the same time, and the survivalist`s children became the Dead Horses, the Vault-dwellers became the Sorrows and (although there is no direct evidence I could find) the Ranger`s children became the White legs.
Is this the story or did I mix it up?

The Vault 22 Overseer (one of them anyway, the one that wrote the "warning") sais that his party has been relentlessly attacked, the Ranger sais it was him... I just can`t understand why they would go at each other like that. I am assuming Vault 22 dwellers started the fight.

Any ideas?

I think you got the horses/sorrows mixed.

I believe the sorrows were the children the survivalist looked after. Could be wrong though.

Not sure about anything else yet.

My suggestion: wait for the people at the vault to figure it out.

The Sorrows are the descendants of the children befriended by the survivalist (Clark). They were escapees from a place they called 'the school'; I think we might see this in Old World Blues.

Clark fought the vault dwellers because they cannibalized an earlier group of Hispanic refugees. From the loot scattered across the area, others have entered but were killed. They had Duffle Bags. Lots & lots of Duffle Bags.

The White Legs are not native to the region. They were promised by Caesar Eddie that they could join his Legion if they 1) destroyed New Canaan and 2) Killed Joshua Graham. They are currently working on #2.

The Dead Horses are here at the behest of Graham; they are not native to the region, either. They helped the New Canaan refugees (who are hiding to the East; we never see them except Daniel & Joshua) escape the White Legs.

That's my take on it. The really confusing thing is that the Sorrows are the only native inhabitants; they were here first, then the Caananite refugees came with the Dead Horses, then the White Legs invaded, then all the Caananites left except for Joshua & Daniel, who stayed behind with the Dead Horses to help the Sorrows. Whew.

have you actually read all the entrys in order?

if you diden't this will help you out figure out what hapened to who

http://fallout.wikia.com/wiki/The_Survivalist

Thanks for the link. Obviously there are far more entries there than what I`ve found.

i was thinking that was probably the case enjoy bro

i populated zion i was bored kidnapped some gamorra girls nad made my own party lol