search the Internet for Otagaki Rengetsu, you'll find a lot of pages describing that fact that she carves poems with her nails on her pottery.
However, there doesn't seem to be much information on what her life was like, so I'd like to touch on that here.
Before we go any further, let me introduce you to one event that made her famous.

From the end of the Tokugawa Shogunate to the Meiji Restoration

“Edo muketsu-kaijo” (meaning, ‘the Tokugawa family bloodlessly surrendered the Edo Castle’), is said to have protected the Edo castle town from the ravages of war.

There is a tale that a poem by Rengetsu influenced the decision of Saigo Takamori, the head of the expeditionary force to the Edo Castle, at that time. Nobody knows how much of an influence her songs had on Saigo, but it is true that she delivered her poems to Saigo on his way to attack Edo castle.

“Ada mikata katsu mo makuru mo awarenari onaji mikuni no hito to omoe ba”
---Foes and friends...whether they win or lose how miserable since I feel they are people of the same land. ---



Rengetsu's personal history

Rengetsu was born in the Sanbongi district of Kyoto on 8th of January, Kansei 3 (1791). She was given the name Nobu (childhood name). The great fire in Kyoto in 1782 is said to have been the catalyst for the birth of Nobu.

As a result of this fire, Kyoto was devastated like the city during the Onin War, and many people were sent to work on reconstruction projects. Her father was among those who had been dispatched to help build the palace and rebuild the Kyoto houses of the various clans. Nobu’s father was a high-ranking Samurai, named Todo Yoshikiyo.

Nobu was born in Sanbongi, in a brothel, and it is said that her mother was a geisha who later married a Samurai from the Kameoka clan. Her mother abandoned Nobu and she was adopted when she was just over 10 days old.

When Nobu was eight years old, her father, Yoshikiyo, died of illness at the young age of 32. There is an anecdote that Yoshikiyo sent a messenger to Nobu to tell her that he wanted to meet her before he died, but Nobu refused to meet him.

Nobu went to work at Kameoka Castle for about 10 years from the age of 8. This is the same clan which her mother married into, but nobody knows if Nobu met her mother.

A big part of Nobu's life was her adopted father, Yamazaki Joemon Teruhisa (later renamed Yamazaki to Otagaki). A little while before Nobu was born, at the time of the reconstruction, Yoshikiyo used Chionin temple as his quarters, and Teruhisa was a Samurai of the temple.

Teruhisa came from a poor farm family and after a lot of hard work, he finally became a retainer of the temple, but he was still poor. Teruhisa was very good at Go and often played games with Yoshikiyo. Eventually, he came to be trusted by Yoshikiyo. One day, Yoshikiyo bowed to him and asked him to adopt Nobu as his daughter, and he accepted.

When New Year's Day was over and the town returned to normal life, he got milk for his adopted daughter from a local woman. However, because he did not charge Yoshikiyo child support, he didn't have enough money to thank the woman for sharing her milk.

At the time, Teruhisa was about thirty-five years old, but he actually had a wife and a son whom he had called from his hometown. In addition, his older sister came along, so he had to support a large family with a small salary. Nonetheless, Teruhisa and his wife raised Nobu as if she were their own true child.


The story of the time of working in Kameoka Castle

Let's return to the story of the time of working in Kameoka Castle. Nobu seemed to be bright and active.

Moreover, after the age of 15, she became more and more beautiful. It was thought that she would soon be favored by a wealthy lord and happily married. However, she did have a major flaw. She was too active and a spirited woman.

She learned poetry, dance, and sewing as a woman needed to in those days. Back then, the only female martial art was Naginata, but this was not enough for her. She wielded a wooden sword, mastered the chain sickle, rode a horse, and even used a bamboo pole to climb over a 1.8-meter-high wall. There is even an anecdote that she threw a thug with her mastery of jujitsu.


■Kameoka castle

The first marriage

After his work at Chionin became highly regarded and his income stabilized, Teruhisa decided to take the Otagaki surname. Yamazaki was the name he was given when he first started working at Chionin, and he originally intended to take the name Otagaki. Even more gratifyingly, when Teruhisa's son became an adult, he began working with Teruhisa at Chionin. The most joyous days for Teruhisa had arrived.Teruhisa wanted his son to marry Nobu. However, his son died of illness at the age of 21. 

Tragically, his wife also passed away shortly afterwards. In order to maintain the family name, Teruhisa adopted a son and when his adopted son became an adult, he gave him the name Mochihiki. When Nobu returned home after leaving her job at the castle, Mochihiki and Nobu married. Three children were born to them, but, devastatingly, one after the other died at an early age. Mochihiki became depressed and turned to alcohol and women. The couple divorced, and Mochihiki later died of illness at his parents' house. Nobu was only 25 years old at the time.

With no successor, Teruhisa continued to work at Chionin Temple even at the age of 64. It may be because she wished to fulfill her father's wish. Nobu remarried at the age of 29. And her new husband, Shigejiro, was said to have been a kind and an ideal husband.Teruhisa happily handed over the reins to Shigejiro and retired. Then they had a girl and later, a boy. All of Teruhisa's anxiety had been rewarded. However, perhaps because of tuberculosis, Shegejiro rapidly became ill and died. It is said that Nobu fell into a coma shortly after her husband's death. On Shigejiro’s deathbed, Nobu cut off her long dark hair to become Nagisage (short hair style for nun). She was only 33 years old.

Become a Buddhist nun

Teruhisa shaved off his hair and decided to become a monk, and asked Chionin to ordain him. He became the head monk of Makuzu-an and was given the Buddhist name of Saishin. After becoming a nun, Nobu was given the Buddhist name of Rengetsu (lotus-moon). With the two children in tow, the family lived in isolated peace. The lotus flowers blooming from the deep mud in the garden pond gave Nobu peace of mind. Her father taught her to play Go, she wrote poetry and spent her days raising her children happily.

But Rengetsu’s happy days did not last long. One of her daughters passed away at the age of 35, and a son passed away at the age of 37.And, with a broken heart, her father, Saishin, passed away at the age of 78. Rengtsu was 42 years old. Chionin is not a nunnery, so they didn't allow her to live there after she lost her father. With nowhere to go, she lived in front of her father's grave, crying almost every day. One day she came to her senses when some village folk reprimanded her strongly that the grave was no place for people to live.