In 1871, Yamakawa was one of five girls chosen to accompany the Iwakura Mission to America and spend ten years receiving an American education.
She learned English and graduated from Hillhouse High School, then attended Vassar College, the first nonwhite student at that fledgling women's university.
When she first returned to Japan, Yamakawa looked for educational or government work, but her options were limited, especially because she could not read or write Japanese.
In April 1882, she accepted a marriage proposal from Ōyama Iwao, a wealthy and important general, despite the fact that he had fought on the opposing side of the Battle of Aizu.
[5] Yamakawa was raised in a traditional samurai household in the town of Wakamatsu, in a several-acre compound near the northern gate of Tsuruga Castle.
[2] She did not attend school, but was taught to read and write at home, as part of a rigorous education in etiquette and obedience based on the eighteenth-century neo-Confucian text Onna Daigaku (Greater Learning for Women).
"[8] It was during the Battle of Aizu that the Byakkotai (White Tiger Brigade), a group of teenage fighters, famously committed mass suicide under the mistaken belief that the castle had fallen.
[8] The 600 women and children inside the castle, led by Matsudaira Teru,[11] formed workgroups to cook, clean, and make gun cartridges,[13] as well as nursing nearly 1,500 wounded soldiers.
[14] One of Yamakawa's sisters attempted to join Nakano Takeko's Shōshitai (娘子隊, "Girls' Army"), but on her mother's orders remained inside the castle making gun cartridges.
[15] In the final days of the siege, Yamakawa's mother sent her and other girls to fly kites as a gesture of defiance while imperial cannons bombarded the castle and the women smothered the shells with wet quilts.
The 17,000 refugees exiled there had no experience of farming, and the winter saw shortages of food, shelter, and firewood which threatened Yamakawa's family with starvation.
[22] Yamakawa was one of five girls sent to spend ten years studying Western ways for the benefit of Japan, after which she was to return and pass on her knowledge to other Japanese women and to her children, in accordance with the Meiji philosophy of "Good Wife, Wise Mother".
[20] In response to Kuroda's second call for girls to be educated in America, Yamakawa's eldest brother Hiroshi, acting as head of the household, nominated her.
Yamakawa and the other girls spent two weeks in San Francisco, largely solitary in their hotel room but the subjects of intense newspaper coverage.
[33] After two weeks in San Francisco, the Iwakura Mission embarked on a monthlong cross-country train tour, arriving in Washington, DC on February 29,[34] where Charles Lanman (secretary to Arinori Mori) took custody of the girls.
[29] Yamakawa lived briefly with Mrs. Lanman's sister, a Mrs. Hepburn,[29] then in May 1872 all five girls were moved to their own house with a governess, to study English and piano.
Nagai enrolled as a special student in the music department, while Yamakawa pursued a full four-year bachelor's degree.
[46] Yamakawa was elected class president for 1879, and invited to join the literary club of the Shakespeare Society, which was "reserved for students of formidable intellect.
[60] When she first returned to Japan, Yamakawa looked for educational or government work, but her options were limited, especially because she could not read or write Japanese.
[63] In January 1882, Yamakawa wrote to Alice Bacon that one of the marriage proposals she had declined was from someone "I might have married for money and position but I resisted the temptation,"[62] whom she later revealed to have been Ōyama Iwao.
He was also a wealthy and important general in the Imperial Japanese Army who had lived in Europe for three years, spoke French, and sought an intelligent and cosmopolitan wife.
[55] In February 1882, Yamakawa played Portia in an amateur production of the final two acts of The Merchant of Venice at a large party, which inspired Iwao to repeat his proposal.
Tokutomi revised the story, and published it as a standalone book in 1900, which is when it became one of the most successful novels at the time, a major bestseller popular across many social groups for its elegant language and tear-jerking scenes.
[26] She frequently hosted American visitors to advance Japanese-American relations, including Alice Bacon, the geographer Ellen Churchill Semple and the novelist Fannie Caldwell Macaulay.
[79] Positive press in 1895, at the conclusion of the First Sino-Japanese War (in which her husband had military victories and she had philanthropic success), returned her to the public eye.
[74] Ōyama assisted Tsuda and Hirobumi Ito in establishing the Peeresses' School in Tokyo for high-ranking ladies,[89] which opened on October 5, 1885.
[91] In its first years, the school was a relatively conservative institution, where aristocratic students dressed in formal court dress and studied Japanese, Chinese literature, English or French, and history alongside the less academic subjects of morals, calligraphy, drawing, sewing, tea ceremony, flower arrangement, household management, and formal etiquette.
[26] At the outbreak of the First Sino-Japanese War in 1894, she formed a committee of sixty aristocratic ladies to raise funds and gather supplies for the troops.
[102] The second book telling the story of Ōyama's life is Daughters of the Samurai: A Journey from East to West and Back, written by Janice P. Nimura and published in 2015.
This biography discusses Ōyama alongside Shige Nagai and Ume Tsuda, who were also educated in America as part of the Iwakura mission.