The Moon Tribe cataclysm was an event said to have wiped out all life on the Moon, with only three people being noted to have escaped. Little is known about the event itself, but its effects on the world of Nippon are profound.
Long, long ago, the people that lived on the Moon in peace, allowed to develop highly advanced technologies and a strong society and culture to live under. They had no known prior connection to any of the other races of Nippon or the Celestial Plain, meaning that there was no sharing of culture, goods, or services until after this event forced the evacuation of a handful of people to various parts of the world below.
Little is known about the true happenings of this catastrophe. Of the three members who survived, Waka escaped using the Ark of Yamato; Kaguya was placed in a rocket and sent to Nippon; and Sugawara's means of escape are unknown. The rest of the race living on the desolate rock was left to perish.
Following the collapse of this race, many of their creations were scattered about Nippon. Modern inventor and local tinkerer Gen notes that he collects these "artifacts" and uses them in his inventions. Daidarabotchi is also hidden within the Underground Ruins nearby Sei'an City, where Gen lives, in the neighboring region of North Ryoshima Coast. The most notable effects of this event, however, are seen in how the survivors manipulated their surroundings to continue their existences.
Using the Ark of Yamato as a rescue ship, Waka was able to escape to the Celestial Plain, where he lived alongside the Celestials and Amaterasu for many years to come. The ship he arrived on was also enshrined on the Celestial Plain until the it was attacked by Orochi, leading up to the Ark of Yamato genocide.
From there, Kamui, the region the Ark crash-landed in, gained its nickname as the "origin of all evil" by being the resting place of the Ark, where new demons spawned from constantly. Waka, however, did not stay in this region for long. It is believed he gave the prophecy that stated the purpose of Kutone before leaving to find Amaterasu, who he had already instructed to drag Orochi to Nippon. While there, he instructed her to wait for the Chosen One before leaving once more to establish the Tao Troopers in Sei'an City.
Following Orochi's defeat, he returned to the region to establish the Moon Shrine which stands in front of the Moon Cave, as a means of ensuring no one ever removed the sacred sword Tsukuyomi. After that, he continued to monitor activities in both Eastern and Western Nippon and protect its many people in the absence of Amaterasu.
Having been only a toddler when this event took place, she has no true memories of the event and instead only recalls the rocket she was placed inside. Ishaku notes the descent strange lights, as told to him by his great-grandfather, along with stories of other sightings like this in one of his travel guides. Whether or not he ever saw Kaguya's rocket fall is unknown. Mr. Bamboo, however, was the one who found her. Upon discovery, the child was freezing and appeared lifeless, hinting that she was near death. Mr. Bamboo then collected the child from the ground as the rocket sank into the earth and took her home to his wife. There, the two worked relentlessly to restore Kaguya to full health and then raise her as if she were their own, having never been able to have children of their own.
Later in Kaguya's life, her adoptive grandmother passed away, leaving her with Mr. Bamboo as her only living relative. However, as he aged, Mr. Bamboo was only able to make the trip to the bamboo forest in Sasa Sanctuary and grew more and more reliant on Kaguya to make the journey to Sei'an City to sell his wares to the people. On her final trip to the capital city, she was captured by a possessed Emperor Takara and forced to remain in a prison cell outside of his home. The reasons for this are unknown, but it was only through the collective work of Amaterasu and Issun, that she was able to be freed. Afterwards, she explains that she recalls being in small room as a very young child and departs to find where a mysterious force is calling her.
Kaguya eventually winds up in the same bamboo forest at Sasa Sanctuary that her adoptive grandfather found her in. With help from Amaterasu, she unearths a massive metal bamboo shoot. She then says her goodbyes to her grandfather, enters the mysterious contraption, and launches into the sky, leaving her grandfather all alone in the world.
It should be noted that Kaguya has not been heard from since.
How Sugawara escaped and to where he went is unknown. However, it is stated that he integrated himself into Sei'an City politics and became a politician himself. However, after being murdered in cold blood following a great deal of in-fighting, his spirit manifested itself as the vengeful King Fury. Sugawara is also the only named member of the Moon Tribe to have survived the Moon Tribe Cataclysm and then die somewhere else.