The Lost Fishhook That Leads to Japan's Imperial Line

The Swap Hoderi, called Umisachihiko, is the brother whose luck is in the sea; Hoori, called Yamasachihiko, has the luck of the mountains. They are grandsons of Amaterasu's grandson, which places them near the top of the divine genealogy.

Hoori proposes they exchange tools for a day. Neither has any success — the luck, it turns out, belongs to the tool and the person together — and worse, Hoori loses the fishhook in the sea. He breaks his own sword and forges five hundred hooks as replacement, then a thousand, and his brother refuses all of them. He wants that hook.

This is an unreasonable demand and the text knows it. The refusal is the engine of the whole story, and it is also a compact statement about a certain kind of relationship between brothers that recurs throughout the mythology.

The Palace Under the Sea Weeping on the shore, Hoori is met by a deity of the tides who builds him a boat and sends him down to the palace of Watatsumi, the sea god. It is described as a place of gates and wells and a tree beside the water — an underwater court, not a cave or a void.

There he meets and marries Toyotama-hime, the sea god's daughter, and stays three years, at which point he remembers what he came for. The sea god summons the fish, finds the hook lodged in the throat of a sea bream, and returns it — along with two jewels that control the tides, and precise instructions for handing the hook back that amount to a curse.

Hoori returns, follows the instructions, and his brother's fortunes collapse. When Hoderi attacks him, Hoori uses the tide jewels to drown him and then to save him, and the brother submits.

The Birth, and the Broken Promise Toyotama-hime follows Hoori to land, pregnant, and asks him to build a birthing hut and — crucially — not to look at her while she gives birth. He looks. She has taken her true form, described in the text as a wani, the same word used for the creatures in the rabbit story.

Ashamed at having been seen, she returns to the sea and seals the boundary between the two realms behind her, leaving the child. Her sister raises him, he marries her, and their son is Jimmu, traditionally counted as the first emperor of Japan.

The structure here should feel familiar: a prohibition on looking, a violation, and a permanent separation between worlds. It is the same shape as Izanagi in the underworld, two generations of narrative earlier, and the repetition is clearly deliberate.

What the Story Establishes Beneath the fairy-tale surface this is a genealogical argument. The imperial line is being given descent from both the sun goddess, through Amaterasu's grandson, and from the sea god, through Toyotama-hime — the sky and the ocean, which for an island polity with maritime interests is a claim about the right to rule both.

The fishhook dispute also reads as a settlement between two ways of life. Hoderi, whose luck was the sea, is subordinated; his descendants are named in the text as a particular coastal people who serve the court. Myths of this kind frequently encode which group ended up on top, and this one is more explicit about it than most.

The Coast Where It Is Set Southern Miyazaki holds the sites. Udo Jingū is built inside a cave in a sea cliff, reached by a walkway cut around the rock face above the water, and is associated with the birthing hut and with Hoori's son — the interior of the cave is a working shrine with the sea audible below it.

The nearby coast has the geology to match the story: Aoshima's island shrine ringed by the washboard rock formations locally called the devil's washboard, and a long stretch of subtropical shoreline that reads as convincingly otherworldly on a bright day. It is one of the least visited parts of Kyūshū by foreign travellers and one of the most atmospheric.