Advancement and reversals within Satsuma
Saigo was born into a lower-ranking samurai family in Kagoshima and advanced under domain lord Shimazu Nariakira. Nariakira's death and the Ansei purge brought severe reversals, including a suicide attempt and periods of enforced island residence at Amami Oshima, Tokunoshima and Okinoerabu.
After returning to political activity, Saigo initially worked on the shogunate's side during the first Choshu expedition, then turned toward its overthrow. The Satsuma-Choshu alliance of 1866 connected him with Kido Takayoshi and others. His position changed through successive crises rather than following a single unchanged strategy.
The Boshin War and departure from government
During the Boshin War, Saigo served as a commander for the new government. Negotiations with Katsu Kaishu secured the transfer of Edo Castle without a siege, though fighting continued elsewhere. He subsequently became a councillor, participated in abolition of the domains and held military responsibilities.
In 1873 the proposal to send him to Korea divided the leadership. Opposition from Okubo Toshimichi, Iwakura Tomomi and others led to postponement. Saigo resigned and returned to Kagoshima. His resignation and later deprivation of official rank survive in the National Archives, documenting the transition from senior official to opponent.
The private schools and the Satsuma rebellion
In Kagoshima, Saigo and his followers organized private schools attracting former samurai dissatisfied with central policies. Local administration increasingly diverged from the government's direction. School supporters attacked a government powder magazine in late January 1877, and the crisis became a war in which Saigo led the insurgent forces.
Fighting spread through areas including Kumamoto and Miyazaki. Government forces gained the advantage, driving the insurgents back to Shiroyama in Kagoshima. Saigo died in the final fighting on September 24, 1877. The conflict marked the breakup of a Restoration alliance amid changes in military organization and the position of former samurai.