Little is known about their past. They have been known to live on the Kikaiga Island (鬼界ヶ島, lit. Island of Demon World) in southern Japan. At some point in the past, Enma-Daiō entrusted the Jigoku Key (地獄の鍵, Jigoku no Kagi) to them to protect it in secrecy; this was achieved by sealing the key within chiefs' bodies. However a group of Western Yōkai led by Backbeard were after the power of Jigoku, detecting the location of the key, resulting in decades of continuous invasions of the island and wars against Kitarō Family protecting Amami Tribe and the island without knowing the real intentions of the foes to attack the island. As no one, including Amami people themselves, were not aware of the true fighting capability, repeated attacks by the foreign yōkai extensively reduced the Amami Tribe to a verge of extinction. As Miu and Kai's mother, the previous chief was also sacrificed in the battle 12 years ago, leaving the siblings as the only survivors.
In the battle 12 years later, the Jigoku Key inside Miu moved to Kitarō when she was trying to save the dying Kitarō, leading him to activate the Jigoku Kyūkyoku Ōgi (地獄究極奥義, lit. "Hell Ultimate Heart"). However, Miu was again targeted by a different group of yōkai to make Kitarō vulnerable.
Little has been known about the biology of Amami Tribe except for aquatic natures including gills on necks and telepathy, and Amami Tribe had been said to be closer to humans in terms of abilities and aging speed. With their calm nature, Amami Tribe was thought to be vulnerable to wars.
However, the secret of the tribe was revealed when Nurarihyon kidnapped and controlled Miu as a trap and a critical weapon against Kitarō for using the strong bond between the two, when he noticed the hidden powers of the race. It was revealed that tribe members indeed can be powerful fighters and are notable even comparing to Kitarō, the descendant of the royal family of Ghost Tribe wearing chanchanko. In a short fight between Miu under control and Kitarō, Miu showed surprising agility, speed, power, and durability. After recovering, Miu has awaken a powerful healing ability which even repairs chanchanko instantly.
- Amami Tribe is likely based on the little known (and presumably almost extinct) Ghost Tribe of the Sea (海の幽霊族, Umi-no-Yūrei-zoku) mentioned in the manga.
- Etymology of both Amami Tribe and Kikaiga Island are likely from Ryukyu Islands; there are Amami Ōshima and Kikaiga Island.
|Tribes and Clans||Amami Tribe • Ghost Tribe • Hi Clan • Kidōshū • Mu Empire|
|Jigoku||13 Kings of the Underworld • Eight Shinigami • Four Treasonous Generals|
|Japanese Yōkai Groups||47 Yōkai Warriors • 808 Tanuki • Azuki Allied Force • Flame Yōkai Five • Kitarō Family • Nurarihyon's Faction • Seven School Mysteries • Shichinin Misaki • Tengu Police|
|Western Yōkai Groups||Western Yōkai Army • Western Yōkai Three|
|Other Yōkai Groups||Ancient Gods • South Asian Yōkai Five • Zodiacs|
|Other Groups||Daidara Order • The Batteries|