History of Spira

[Squall of SeeD]

That's accurate with one exception, SeeDRankLou:

(SPOILER)A summoner named Yunalesca, one of the survivors from Zanarkand, devised a way to defeat Sin. She turned her husband Zaon into a fayth, and the bond they shared alouded her summon a truely awesome aeon, know in the present as the final summoning, and it defeated Sin. But unknown to her would be the two consequences of doing this.

(SPOILER)According to Maechen, Yunalesca was Yu Yevon's daughter and likely knew full well what would happen, and even intended it to be so:

(SPOILER)Maechen
"Rumors flew in Bevelle about Sin's sudden appearance."
"They said that the people of Zanarkand became the fayth, that they had called Sin."
"And that the man responsible..."
"was none other than the summoner Yevon, ruler of Zanarkand!"
"Yes, the lord father of Lady Yunalesca."
"On the eve of Zanarkand's destruction, Lady Yunalesca..."
"had fled to safety with her husband, Zaon."
"Later, the two used the Final Summoning to defeat Sin."
"Yet the people of Bevelle still feared Yu Yevon."
"It was to quell his wrath that they revered him, and first spread his teachings."
"And so were born the temples of Yevon."
"I suppose it's possible Yunalesca had planned it that way from the start!"
"A fair trade, she defeats Sin in exchange for her lord father's honor."
"Of course, there's no proof. No, the facts are lost in the mists of time."
"And who'd admit Yevon was an enemy of Bevelle?"
"You can bet the temples had a hand in covering that one up!"
"And that, as they say, is that."

Otherwise, great job!