He was born in the castle town of Saga in Hizen, second son of Edayoshi Nango, a teacher at the domain school Kodokan. His father, versed in national learning, preached loyalty centered on the emperor, and his elder brother Edayoshi Shin'yo later became a Kodokan professor; both strongly shaped him.
When his brother Shin'yo formed the Gisai Domei to honor Kusunoki Masashige, loyal servant of the emperor in the Nanbokucho period, Taneomi led it with him. Young men such as Eto Shinpei, Oki Takato and Shima Yoshitake joined, and Saga's future Restoration leaders grew from it.
He went to Kyoto to study the imperial tradition and Japanese classics, debating with many national-learning scholars, and learned there of the arrival of Perry's black ships the next year. On a later stay he urged the court to have Saga troops sent to Kyoto, but the lord rejected this and confined him.
In this year his father died, and he was adopted by the Saga retainer Soejima Toshitada, taking the Soejima name and marrying Ritsuko. Released from confinement, he taught at the Kodokan, among others Okuma Shigenobu. Three years later his brother died of cholera, and his brother's pupils came to look up to him.
In Nagasaki he studied English and American government with Okuma Shigenobu under the missionary Verbeck, and taught Japanese and Chinese learning at Saga's English school Chienkan. He also went to Kyoto to urge a shogunate official to return power to the emperor, but was rebuffed and confined again.
He became a councillor of the new Meiji government and, as a judge in the bureau of institutions, wrote with Fukuoka Takachika the Seitaisho setting out the new government's structure. Drawing on American institutions and Fukuzawa Yukichi's Seiyo Jijo, it adopted the idea of separating powers. The next year he became one of the first sangi councillors.
As the Iwakura Mission left for the West, he took over as foreign minister. In the border dispute with Russia over Sakhalin he proposed buying the whole island, but this was not realized; he is said to have regretted all his life that Sakhalin was later given up.
A Chinese man fled the Peruvian ship Maria Luz in Yokohama, revealing that the Chinese aboard were treated like slaves. On humanitarian grounds Soejima had the case tried and freed 229 Chinese, handing them over to Qing China. The decision was later upheld by international arbitration.
As ambassador plenipotentiary he went to Qing China, exchanged ratifications of the Sino-Japanese friendship treaty, and was granted a private audience with the Tongzhi Emperor in Beijing. Back home, in the Meiji 6 political crisis over sending an envoy to Korea, he left the government with Saigo Takamori, Itagaki Taisuke and others.
Itagaki Taisuke, Goto Shojiro, Eto Shinpei and others gathered at his home to form the Aikoku Koto party and submitted a petition for an elected assembly to the government. Urged to return to Saga with Eto, he stayed in Tokyo at Itagaki's persuasion.
He sailed from Yokohama to Shanghai and traveled across China for about two years, visiting Suzhou and Hangzhou. In Tianjin he met Li Hongzhang, who urged him to serve the Qing, but he declined. Exchanging poems with literati everywhere, he honed the skill that would leave over 2,000 Chinese poems.
He became first-class tutor in the Imperial Household Ministry, lecturing Emperor Meiji on the Confucian classics. Despite a move by Kuroda Kiyotaka to remove him, he continued after receiving a letter from the emperor, lecturing until the post was abolished. The emperor trusted him deeply.
He moved from vice-president of the Privy Council to home minister in Matsukata Masayoshi's cabinet, but resigned within three months over conflicts in the government. The year before he had become head of the Toho Kyokai and worked for exchange with Asian peoples; the Qing thinker Liang Qichao later visited him in Japan.
He died of illness in Tokyo during the Russo-Japanese War. Known as a calligrapher under the name Sokai, his free and powerful brushwork left a great mark on modern calligraphy. Itagaki Taisuke praised him as the man who should have been chancellor of the realm.
Kusunoki MasashigeSaigō TakamoriEtō ShinpeiFukuzawa YukichiMatsukata MasayoshiItagaki TaisukeŌkuma ShigenobuGoto Shojiro
Iwakura TomomiWilliam S. ClarkKanō HōgaiTakahashi YuichiNishi AmaneYuri KimimasaŌkubo ToshimichiKawanabe Kyōsai
People of the Meiji period ・ People by period
Based on facts found in textbooks and biographies. Uncertain points are marked as such.