Japanese family tree

This tree has an ending that no other tree here has: it terminates in a historical royal house. The two eighth-century chronicles that record it were commissioned precisely to establish that descent, and every line above the final generations exists to make the last one legitimate. Read it as an argument and the structure becomes obvious.

From formlessness to a couple

The chronicles open with something closer to a list than a story. Kami come into being alone in the plain of high heaven and immediately conceal themselves; then several generations arise, some singly and some in pairs, most of whom do nothing whatever. This upper section of the diagram is a preamble, and the sources treat it as one.

The tree becomes narrative with Izanagi and Izanami, the seventh pair, who are sent to consolidate the drifting land. They stir the brine with a jewelled spear, and the drip that falls from its tip becomes the first island. Their marriage produces the islands of Japan and a large number of kami.

It also produces the first mistake in the corpus. At their wedding the woman speaks first, and the resulting child is malformed and set adrift; they consult, repeat the ceremony with the man speaking first, and it succeeds. The tree marks that first child, because the chronicles do.

The break, and the three who follow

Izanami dies giving birth to fire and goes to Yomi, the land of the dead. Izanagi follows and is told not to look at her; he looks, sees corruption, and flees, and they part at the boundary rock as enemies, with her promising to kill a thousand people a day and him promising fifteen hundred births.

The three most important kami are then produced by neither parent together. Purifying himself after the journey, Izanagi washes his left eye and Amaterasu, the sun, is born; his right eye and Tsukuyomi, the moon; his nose and Susanoo, the storm. The diagram draws these as descent from Izanagi alone, which is exactly what the sources describe, and it is worth noticing that the central line of the whole tree comes from an act of ritual cleansing rather than a union.

The contest that produces the imperial line

Amaterasu and Susanoo's quarrel produces children by a procedure with no parallel elsewhere on this site: they exchange objects and produce offspring from them. She takes his sword, breaks it, chews it and breathes out three goddesses; he takes her string of beads, does the same, and produces five male kami. Both then claim victory on the terms they had set.

The crucial genealogical consequence is that the male kami born from Amaterasu's beads are counted as hers, and the imperial descent runs through one of them, Ame-no-Oshihomimi, to his son Ninigi, the grandson who is sent down to rule the land. Ninigi's descendants become the emperors, with Jimmu conventionally the first.

The three regalia — the mirror, the sword and the jewel — pass down this line, and the diagram treats them as an inherited property that identifies the branch.

The Izumo line the chronicles could not leave out

Running parallel is a second dynasty the chronicles cannot ignore. Susanoo, exiled to earth, kills the eight-headed serpent Yamata-no-Orochi and finds a sword in its tail. His descendant Ōkuninushi rules the land, survives a long sequence of murders by his brothers, and is finally required to hand the country over to the heavenly kami — receiving, in compensation, a great shrine at Izumo.

That is a political settlement between two real regional powers, recorded as genealogy. The diagram shows the Izumo branch in full rather than as a footnote, because the chronicles devote enormous space to it precisely because it had to be dealt with.

Where the two chronicles differ

• Order of birth. The Kojiki and the Nihon Shoki do not always agree on the sequence of the earliest kami, and the Nihon Shoki frequently prints several versions of the same generation with "in one writing it is said".
• Tsukuyomi. The moon kami is born in the central line and then almost vanishes. In one Nihon Shoki variant he kills a food goddess, an episode the Kojiki assigns to Susanoo instead.
• Ōkuninushi's descent from Susanoo is given at different removes in different texts — son in some, several generations down in others.
• Whether Izanami's death precedes or follows certain births varies, which shifts which kami count as the couple's joint offspring.

The diagram marks each of these with the chronicle that carries the alternative, since here the disagreement is between two named books rather than a diffuse tradition.

Reading the diagram

Solid lines are relationships both chronicles support. Broken lines carry the variant and name the source. Births by non-sexual means — from an eye, a nose, a chewed object, a discarded staff — are drawn as descent and labelled, because they are descent in the logic of the text.

The tree deliberately stops where the chronicles stop being mythological, at the first emperors, and it makes no claim about that boundary's historicity; the Japanese tradition hub explains why the boundary is drawn where it is and what the chronicles were commissioned to do.