For 20 years, it has been under Ibara's reign of terror; he abused the Petrification Weapon to petrify anyone who defies him in the slightest.
They would sometimes hold a harem selection ceremony where the most beautiful women of the island would be paired with a warrior.
During Ibara's reign, it was forbidden to create new things, as Ibara feared the possibility of usurpation. He also prevented escape, as he would be without subjects to rule and had his warriors punish those who tried, such as with Amaryllis and her friends.
Now that Soyuz has become leader, it is likely that Ibara's tyrannical laws have been repealed, though it is unknown if Soyuz plans to make any new rules of his own.
The kingdom was founded by the descendants of the astronauts who were the only known humans to not be petrified. Since that time, some chose to leave the island, eventually populating mainland Japan and create Ishigami Village.
Centuries after the petrification event, several of the Petrification Weapon rained down from the sky. Brigades sought to use them to conquer the island but a majority of the weapons were destroyed by a warrior that soon lost his life but his servant Matsukaze carried on his work.
Matsukaze was able to destroy most of the devices but one device remained. Wanting to warn future generations, Matsukaze petrified himself. The last weapon ended up in the hands of the brigades and was passed down.
17 years prior to the start of the series, Ibara petrified Soyuz's father to claim the throne for himself. Ibara tried to kill Soyuz because the infant witnessed the assassination. However, Soyuz's mother took the child and fled the island with him. She was wounded and ultimately died but her son ended up leaving the island, washing up in Ishigami Village.
In the year 5736, Amaryllis and some of her friends tried to flee the island but were caught sneaking out by Kirisame and Mozu who used the Petrification Weapon to petrify them but Amaryllis managed to escape.
Later, the Kingdom of Science exposed Ibara's crimes, with the mad minister petrifying all those on the island. All except for Senku and Ibara were petrified but using his wits, Senku ultimately petrified Ibara. Senku and his comrades then revived all those of the kingdom and explained Ibara's deception. They also revived people petrified from centuries ago, such as Matsukaze. Soyuz ultimately stayed on Treasure Island, to take his rightful place as the kingdom's ruler and revive all who were petrified. The Petrification Kingdom also became part of the Kingdom of Science.
- Matsukaze's master (Deceased)
- Head of Petrification Kingdom (Petrified, deceased)
- Soyuz's mother (Deceased)
- Ibara (Petrified)
|Nations||Kingdom of Science • Tsukasa Empire • Petrification Kingdom • American Colony|
|Settlements||Ishigami Village • Treasure Island|
|Landmarks||The Great Buddha of Kamakura • Cave of Miracles • Camphor Tree • Hiromi College • Hirosue High • Roppongi Hills Mori Tower|