He was born at Marugame in Kagawa, the eldest son of army officer Osugi Azuma. With his father's transfer he moved as a small child to Shibata in Niigata and grew up there. Raised in a garrison town, the boy aimed to become a soldier himself.
He entered the army cadet school in Nagoya. But he could not adapt to its rule-bound life and is said to have been punished repeatedly for defiance. In the school he entered to become a soldier, a strong revulsion toward authority and orders grew instead.
Partly after being badly injured in a fight with classmates, he was expelled from the cadet school. His road to soldiering closed, Osugi went to Tokyo and began studying languages. It was a turning point that changed the direction of his life.
He entered the French department of the Tokyo School of Foreign Languages. Around this time he frequented the Heiminsha of Kotoku Shusui and Sakai Toshihiko and encountered socialist ideas. Sympathizing with their opposition to the Russo-Japanese War, he moved toward social activism.
Joining a movement against higher Tokyo streetcar fares, he was arrested and jailed for the first time. Jailed many times afterward, he is said to have resolved to learn one foreign language each term, calling it one crime, one language.
At a socialist gathering, he clashed with police after marching into the street with red flags and was arrested in the Red Flag Incident, receiving a sentence of about two and a half years. As a result he was in prison during the High Treason Incident of 1910 and escaped while many comrades were charged.
In the winter period of harsh suppression after the High Treason Incident, he launched the magazine Kindai shiso with Arahata Kanson. Through literature and ideas, he argued for individual freedom and thinking for oneself, influencing young readers.
Though married, he was involved with Kamichika Ichiko and Ito Noe, and at the Hikage teahouse in Hayama he was badly wounded with a blade by Kamichika. The scandal shocked the public, and many comrades distanced themselves. He then lived with Ito Noe.
He translated and published the first volume of the French naturalist Fabre's Souvenirs entomologiques in Japanese. He is said to have been strongly drawn to a book closely observing the lives of small creatures. At the end of that year he secretly went to France to attend an international meeting.
He spoke at a May Day rally at Saint-Denis near Paris and was arrested by the French police. Found to have entered without a passport, he was deported and returned to Japan. His actions seeking freedom did not change even abroad.
In the chaos after the Great Kanto Earthquake, he was taken away by military police with Ito Noe and his young nephew, and all three were killed. He was 38. This Amakasu Incident is still questioned in history as a case of military power unjustly taking individual lives.
Kōtoku ShūsuiSakai ToshihikoItō Noe
Shiga NaoyaTakehisa YumejiKitahara HakushūMushanokōji SaneatsuHiratsuka RaichōMatsui SumakoYamada KōsakuHagiwara Sakutarō
People of the Taishō period ・ People by period
Based on facts found in textbooks and biographies. Uncertain points are marked as such.