Kozaisho (1164? - April 3, 1184 was a woman who lived at the end of the Heian period. She was a daughter of the Gyobukyo (Minister of Justice), FUJIWARA no Norikata. She was a wife of TAIRA no Michimori.
An episode in which Michimori dies in the Battle of Ichinotani and his wife Kozaisho drowned herself following her husband became a symbolic tragedy of the Battle of Ichnotani and covered an entire chapter of the classical war chronicle, "The Tale of the Heike."
Kozaisho was a court lady who served Imperial Princess Muneko (Imperial princess of Emperor Toba and an elder sister of Emperor Goshirakawa) and was said to be the most beautiful woman in the court at the time. At the time she accompanied the Imperial Princess who went to see the cherry blossoms at Hosho-ji Temple when Kozaisho was 16 years old (around 1179?), the Assistant Master of the Consort's Household Michimori saw Kozaisho and fell in love with her at first sight. After that, he sent her waka poems and love letters at brief intervals; however, over a period of 3 years, Kozaisho never replied to him.
He wrote a letter to her thinking it would be the last one and handed it to a messenger; however, unluckily there was no usherette at her place at the time the messenger visited.
When the messenger was on the way back, he happened to meet Kozaisho in her carriage as she was returning to the palace from her home
The messenger threw the letter into her carriage and left. Kozaisho took the letter tentatively; however, she mistakenly dropped it just in front of Josaimonin (Imperial Princess Muneko) when served, and Josaimonin picked it up and said "Too much strong-mindedness is not favored" citing an example of ONO no Komachi who was said to have died a miserable death, and Josaimonin ordered an ink stone to be brought and prompted Kozaisho to write a reply to him.
In this way, Michimori and Kozaisho were united after the mediation of Josaimonin. The couple was very happy together, as they were united after a romantic relationship. In addition to marrying Kozaisho, Michimori married a daughter of his cousin, TAIRA no Munemori, out of political necessity. However, this wife was only a little girl of 12 something, and therefore he never became intimate with her.
Before long, the Jisho-Juei War broke out and Michimori fought in one place after another; however, the Heike clan suffered a crushing loss to MINAMOTO no Yoshinaka, and in 1183, they were finally forced out from Kyo (the capital, namely Kyoto.)
Kozaisho drifted on a boat at sea with Michimori. The Heike clan placed its headquarters at Yashima, Sanuki Province (today's Kagawa Province) and then fought back to Fukuhara-kyo (the capital once the Heike clan transferred from Kyoto), Settsu Province (around today's Hyogo and Kyoto prefectures).
In February 1184, Yoshinaka was defeated by younger brothers of MINAMOTO no Yoritomo in Kamakura, MINAMOTO no Noriyori and MINAMOTO no Yoshitsune. In March of the year, Noriyori and Yoshitsune closed in on Fukuhara leading a large army. Before the battle began, Michimori called his wife on a fleet of boats offshore to his base and said to her that "I feel like I might die in the battle tomorrow."
What would you do if it comes true?"
Kozaisho did not believe his words, as the battles had become everyday business, and she told him that she was pregnant. Yorimichi said with great delight that "Now I'm 30 years old I want a boy (as an heir) if it's true. How many months are you pregnant? I'm worried that you are on a boat."
Then his younger brother, TAIRA no Noritsune, who was known as one of the best men of adamantine courage among the Heike clan, appeared. He ticked off his elder brother, saying with anger, "Here is such a dangerous place among the battlefield where a man like me is posted. In such a mind-set, you can't do your job well." Michimori thought that his brother's words were right and let his wife go back to the fleet.
The battle ended in pasting of the Heike clan; a number of soldiers of the clan died and Michimori never returned to his boat.
On the way back to Yashima, although Kozaisho heard that her husband had been killed, she waited helplessly for his return to the fleet, thinking it must have been wrong and there was a possibility that he would return alive.
A squire of Michimori, Tokikazu TAKIGUCHI, came to her boat and reported that Michimori was killed at Minatogawa after his last brave struggle. Having heard this, Kozaisho could not respond to it; she was dissolved in tears and she could not get up by the time dawn broke.
On the night of April 3, when the fleet reached Yashima, Kozaisho said to her nanny that "There is no one who met my husband after the Battle of Minatogawa. I'm prepared to believe my husband's death"; she then talked about the last time she saw her husband at Fukuhara, saying and asking that "Though I think I must have my baby and raise it to keep in memory of him, my sorrow only grows stronger and I'm prepared to sink deep in the sea instead of suffering from the sadness I feel for my dead husband. Please pray to Buddha for my late husband and me."
The nanny held back her tears and said "You should have baby to raise it and you should keep on living as a nun" and tried desperately to stop Kozaisho. Then Kozaisho replied that as if she held back at the time saying, "No one actually drowns oneself after saying to do so."
However, when the nanny fell into a short sleep, Kozaisho got up and recited Buddhist invocation that "I believe in the Western Land of Utmost Bliss…. Please let my husband and myself meet in Paradise," and threw herself into the sea.
The steerer of the boat watched this and woke up the nanny; all the people searched for her in the sea and finally found Kozaisho and pulled her up on the boat; however, she was already dead. The nanny invested her body with the armor of Michimori and sank it in the sea with tears. After this incident, the nanny tonsured and became a nun under a younger brother of Michimori, Chunagon (vice-councilor of state) Chukai RITSUSHI (Buddhist priest) who became a priest, and she prayed to Buddha for the happiness of Michimori and Kozaisho.
People were very impressed with this case; although wives who were bereaved of their husbands usually became nuns, Kozaisho following her husband was remarkable; people said to each other that "Royal subjects never serve two Kings and chaste wives never marry two husbands" (citing tradition from "Shiki," Chinese history book.)
Also in "Kenrei Monin Ukyo no Daibu Shu" (The poetic Memoirs of Lady Daibu), there is an entry that a rumor earned popularity in Kyoto that a court lady who was famous for her beauty served Josaimonin, became a wife of Michimori, and followed after her husband when he died with the words, "What a strong tie of a husband and a wife that has never ever been."