Fish-Man Island

Biodata

Feature	Details
Name	Fish-Man Island (鱼人岛)
Type	Undersea island and sovereign nation
Location	A massive hollow beneath the Red Line, approximately 10,000 meters below sea level 416
Inhabitants	Primarily Fish-men and Merfolk; five million residents were evacuated during the island's collapse crisis 563
Leadership	King Neptune and Ryugu Palace; Bright and Jinbe also jointly deliberate major national affairs 149 237
Role	A principal route between Paradise and the New World, as most travelers cannot use Mary Geoise 33
Status	The original island was evacuated and left deserted; its displaced population established the temporary settlement of New Fish-Man Island in the New World 563 568
First Appearance	Chapter 1 1

Background / History

Fish-Man Island was long vulnerable despite being the homeland of Fish-men and Merfolk. Its position on the main Grand Line route brought merchants, pirates, underworld figures, and settlers through its waters, while lax entry controls enabled slave traders to disguise themselves as merchants and abduct Mermaids. 33

King Neptune appointed Bright to establish an Immigration Bureau and organize a mining company. Bright presented the reforms as a means to strengthen Fish-Man Island rather than overthrow Ryugu Palace, though Arlong initially favored direct confrontation with the royal government. 39

The Immigration Bureau recruited 10,000 Fish-men and Merfolk in three days. Jinbe trained the recruits at the Sea Forest, and the organization formally began operations after more than a month of training. 40 49

Bright's administration transformed the island's economy through seabed mining, manufacturing, trade, and security reforms. The Fish-Man District, formerly impoverished and dominated by gangs, gained sanitation work, rebuilt housing, mining employment, and new businesses. 70

Appearance

Before its evacuation, Fish-Man Island was a sunlit undersea nation enclosed in a gigantic bubble. Light and warmth filtered down from the Eve Tree of the Sun, allowing its cities, ports, factories, and coral-filled waters to flourish in the deep sea. 416

• It stood inside a vast cavity beneath the Red Line rather than directly on the open seafloor. 416
• A giant bubble supplied breathable air and separated its inhabited areas from the surrounding deep-sea pressure. 416
• The Sea Forest served as a scenic and strategically restricted district; it housed a Poneglyph and later concealed major construction projects. 91 427
• Coral Hill and the Mermaid Cafe became busy commercial and tourist areas as trade expanded. 70
• Its port was enlarged to accommodate merchant traffic, though ships still crowded the docks during the mining boom. 70

Government and Security

Immigration Bureau

The Immigration Bureau was established as a military and border-control force with standing comparable to the Ryugu Palace army. Its initial 10,000 recruits came largely from the Fish-Man District; expansion later raised its personnel to 30,000. 40 49 70

Unit / Measure	Function
External patrol divisions	Half of the Bureau's manpower patrolled outside the island, intercepting incoming ships for inspection or combat. 49
Gate division	Conducted secondary inspections, registration, and admission procedures at Fish-Man Island's entrance. 49
Pass system	Visitors received photographed, expiration-dated passes; those without them were treated as illegal intruders and expelled. 50
Ship inspections	Patrols searched vessels, questioned crews, confiscated weapons during visits, and issued inspection receipts. 50
X-ray screening	A government-purchased X-ray machine was installed at the entrance to inspect inbound and outbound ships. 70

“We are the blade of Fish-Man Island, and we will cut down every enemy who dares invade!” 49

Military Development

• Blue-uniformed Bureau soldiers were equipped mainly with daggers and spears; firearms saw limited deep-sea use. 49
• Sea Beasts supported patrols, inspections, transport, and combat, although their limited numbers strained the Bureau's expansion. 70
• Jinbe oversaw Fish-Man Karate and Haki instruction for Bureau captains, who were expected to pass their training on to subordinates. 49
• By the Sea King riot, all Captain-level Bureau officers had mastered both Armament and Observation Haki, while junior officers and schoolchildren were beginning to awaken Haki through formal instruction. 333
• Fish-Man Island later fielded underwater warships capable of destroying an enemy fleet with torpedo volleys. 147

Economy and Infrastructure

• Seabed mining — High-quality iron ore became the first major export under Bright's administration. Human merchants supplied goods in return for inexpensive ore, making Fish-Man Island a significant commercial partner. 53 59
• Steel production — Fish-Man Island Steelworks began operating after coal deposits were discovered, allowing domestic steel production. Bubble technology mitigated heat, cooling, and pollution problems. 70
• Supporting industries — Coal washing, coking, weapon production, processing plants, and pharmaceutical manufacturing were established alongside the steelworks. 70
• Weapons manufacturing — Early factories produced cold weapons such as swords; Master Tom later agreed to help build an armory after recognizing the island's need for self-defense. 70 108
• International trade — Fish-Man Island established a trade zone with Dressrosa, Prodence, and other nations, investing capital and factory technology in allied countries. 140
• Logistics — Fish-Man Island Logistics grew into a dominant deep-sea shipping enterprise whose revenue became one of the island's largest sources of wealth. 466
• Mineral exports — Seabed mineral trading remained highly profitable, with even the World Government purchasing Fish-Man Island minerals for their quality and low price. 466

External Relations and Reputation

Fish-Man Island's stricter border policy did not amount to blanket exclusion of humans. Legitimate visitors could enter after inspection and registration, while expanded trade gave Fish-men, Merfolk, and humans greater contact and gradually improved mutual perceptions. 50 70

Bright and Dragon formed an alliance between Fish-Man Island and the Revolutionary Army, agreeing to oppose the World Government and pursue a new order. 133

Tesoro's film, Ten Thousand Meters Deep Love, presented Fish-Man Island's prosperity, natural beauty, friendliness, military strength, and the possibility of human–Merfolk understanding to audiences worldwide. The World Economic News Agency promoted its release across the seas, making the island far more widely known. 183 190

The World Government viewed this growing influence as dangerous. It attempted to counter Fish-Man Island's deep-sea advantage through a potion that gave humans Fish-man-like underwater mobility, then sent infiltrators to investigate its industries and target Master Tom and Dyna Stone. 380 416

Crisis and Migration

The destruction of the Eve Tree of the Sun deprived Fish-Man Island of its light and warmth, throwing the population into confusion and making continued habitation increasingly untenable. 529

Im later attacked by destroying the Red Line, threatening to bury the island beneath falling debris. Bright used his awakened power to catch collapsing rock with Flame Clouds while Shirahoshi gathered the Sea Kings. 556

Bright ordered a full evacuation rather than risk the population's destruction. Sea Kings led by Alexander helped defend the island, while Neptune and Queen Otohime organized the residents' departure. 557

The Ark of Promises departed carrying all five million residents, escorted by colossal Sea Kings, the Fish-Man Island army, Ryugu Palace troops, and the Immigration Bureau's Sea Beast units. The original island's streets, mines, and factories were left silent and abandoned. 563

New Fish-Man Island

The refugees settled temporarily on a large, uninhabited New World island with enough land to accommodate the population. Fish-men and Merfolk were free to establish homes both on land and beneath the nearby sea. 566

• Noah remained offshore as the population's primary residence until permanent housing could be built. 566
• Sea Kings blocked the surrounding waters, while signal jammers restricted outside communications during the transition. 564 566
• The settlers experienced the true sun and sea breeze for the first time, fulfilling a dream Fish-Man Island had held for eight centuries. 566
• Bright and Neptune named the temporary homeland New Fish-Man Island. 568