Kami-umi (a myth about giving birth to gods) (神産み)
In Japanese myths, Kami-umi refers to Izanagi and Izanami's giving birth to numerous gods after they gave birth to various islands (Kuni-umi [a myth about the birth of the land of Japan]).
Kojiki (Records of Ancient Matters)
Izanagi and Izanami produced numerous gods, but when Izanami gave birth to the fire god Kagutsuchi, she died from the burns. Having lost his beloved wife and full of rage, Izanagi slew Kagutsuchi no kami (written in 迦具土 or 加具土 in Chinese characters) with Totsuka no Tsurugi (literally, "the ten-hands-long sword").
(Other gods came into being from the blood on the sword as it dripped off.)
Izanagi went down to Yomi (the land of the dead) to look for Izanami, but found that she had already been completely changed from her former self. Shuddering at this, Izanagi fled. Izanagi performed a purification ceremony to cleanse himself of the pollution he had taken on in the Yomi. Various gods also came into being on this occasion. Amaterasu (the Sun Goddess, ruling Takamanohara [the plain of high heaven]), Tsukuyomi (the deity of the Moon, ruling over the night) and Susano (ruling the sea) were born last and were called the three noble gods. They were ordered by Izanagi to rule the world.
Kami-umi
After they finished bearing the Oyashima no kuni (Eight Great Islands) and other small islands, Izanagi and Izanami gave birth to gods. The gods that came into being here were related with nature, such as the six gods to protect the household, the god of wind, the god of trees, and the god of fields.
However, Izanami became ill because her genitals were burned when she gave birth to a fire god, Kagutsuchi no kami. Although Izanami was still suffering from her illness, she continued to produce gods one after another from her vomit and others.
The Fire-Deity Killed
Izanagi wept at the death of Izanami. Other gods were born from these tears.
Then, Izanagi buried Izanami on Mt. Hibanoyama, located at the boundary between Izumo Province and Hoki Province (the present-day Yasugi City, Shimane Prefecture). Out of fury at losing his beloved wife, Izanagi killed Kagutsuchi no kami with a Totsuka no Tsurugi sword. There other gods came into being from the blood on the sword again. This Totsuka no Tsurugi sword was called 'Ame no o habari' (天之尾羽張), or Itsu no o habari (伊都之尾羽張).
In addition, some gods also came into being from the body of lost Kagutsuchi no kami.
Yominokuni (The Land of The Dead)
Izanagi went down to Yominokuni to get Izanami back.
Arriving in Yomi, Izanagi called to Izanami from the other side of a door:
You know, the lands we were creating together haven't been completed, so let's go back.'
Izanami answered: 'I cannot come back to life because I have already eaten food of the Yominokuni.'
(Note: It was thought that if people ate anything from Yominokuni, they would become inhabitants of the Yomi.)
(This is called 'Yomotsu-hegui.')
In addition, Izanami said, 'I'll discuss it with the god of Yomi, but I beg you, please don't look at me,' then went back into the building.
After quite a long time Izanami still had not returned, Izanagi could not wait anymore. He broke the teeth off a comb called Yutsutsuna-kushi, which he was wearing in his left hair-bunch (mizura, a male hairstyle), lit a fire with them, and looked into the building. Izanami did not look like beautiful Izanami any more. Her body was rotted and full of maggots, her voice strangled and choked, and on top of that, eight thunder gods were clinging to her body.
Shuddering with fear at the sight of her, Izanagi tried to run back. However, Izanami felt shame at her repulsive appearance being seen, and commanded Yomotsu-shikome (a hag from Yomi) and had her chase Izanagi.
Izanagi threw away the vine loop that was wearing on his head. Then bunches of grapes grew on it to make him run away while Yomotsu-shikome was eating them. However, she still chased him; he threw the bamboo comb called Yutsutsuna-kushi, which he was wearing in his right hair-bunch. Then bamboo shoots sprouted up in an instant to make him run away while Yomotsu-shikome was eating them.
In addition, however, Izanami had the aforementioned eight thunder gods and a horde of the soldiers of Yominokuni (the army of the land of the dead) chase after Izanagi. Even though Izanagi ran away, keeping them back with a Totsuka no Tsurugi sword, they still kept following him. When he reached the foot of Yomotsu Hirasaka (the slope that leads to the land of the dead), where was the boundary between the Yominokuni and this world, he picked three peaches there to throw them at the pursuers. Then, the pursuers, the spirits of the Yominokuni, fled back.
Here, Izanagi said the peaches 'please help people as well when they are in trouble,' and named them Okamuzumi no mikoto.
In the end, Izanami herself pursued him. Izanagi closed off the Yomotsu Hirasaka using such a huge boulder that would take a thousand people to move it, so that no evil spirits could come out. Facing each other, being on either side of the boulder, this couple would separate.
At this time, Izanami said, 'I will kill 1000 people a day from now on.'
In response, Izanagi said, 'Then I will have 1500 babies born each day, so that they will never die out.'
This shows the original reason why people are born and die.
In addition, because of this event, Izanami is also called Yomotsu Okami (the great god of the Yominokuni) or Chishiki no Okami (the god who caught up [with Izanagi]), and the boulder that was used to close the Yomotsu Hirasaka off is called Chikaeshi no Okami (the god to the way back to the Yominokuni) or Yomito no Okami (the god of the door to the Yominokuni). Furthermore, the Kojiki has Yomotsu Hirasaka at the Ifuya no saka pass in Izumo Province (the present-day Higashi Izumo Town, Shimane Prefecture).
Purification Ceremony and the Birth of Mihashira no uzuno miko (three noble children)
Izanagi went to Awaaki-hara by the river-mouth of Tachibana of Himuka in Tsukushi and performed a purification ceremony to purify himself from the Yominokuni's impurity. 12 gods came into being as he took off what he had been wearing.
When he first dove into the middle stream to purify his body, saying, 'The upper stream flows too swift and down stream too weak,' two gods came into being. These two gods was born from the impurity of the Yominokuni.
Next, he tried to heal the evil, and another three gods were born.
Another two gods were born by his purifying himself at the bottom of the water.
Another two gods were born by his purifying himself in the middle of the water.
Another two gods were born by his purifying himself on the surface of the water.
Sokotsu Watatsumi no Kami (the sea god of the bottom part), Nakatsu Watatsumi no Kami (the sea god of the middle part) and Uwatsu Watatsumi no Kami (the sea god of the upper part) are the gods that people such as the Azumi no Muraji (title given to bureaucrats charged with the imperial table in the seventh century, which was hereditary and reserved for the Azuchi family) believed in who were the descendants of Utsushi Hikana Saku no Mikoto, the son of these three gods. Sokotsutsu no O no Kami (the god of navigation at the bottom), Nakatsutsu no O no Kami (the god of navigation in the middle) and Uwatsutsu no O no Kami (the god of navigation in the upper) are the three great gods of Sumie (Sumiyoshi-taisha Shrine) (Sumiyoshi Sanjin [Sumiyoshi three gods]).
See also the article of Haraedo no okami.
Next, Amaterasu Omikami (the Sun Goddess) was born by his washing his left eye. Tsukuyomi (Tsukuyomi no Mikoto, literally "Moon Reader") was born by his washing his right eye. Susano (Takehaya Susano no Mikoto) was born by his washing his nose. Izanagi was delighted that he got Mihashira no uzuno miko at last, and handed a necklace of beads to Amaterasu Omikami and entrusted Takamanohara (the plain of high heaven) to her. The necklace of beads is called Mikura Tana no Kami. Then he entrusted Tsukuyomi no Mikoto with the Yoru no Osukuni (the realm of the night) and Takehaya Susano no Mikoto with the ocean.