The Satsuma daimyō of the 1850s, Shimazu Nariakira, was very interested in Western thought and technology, and sought to open the country.
At the time, contacts with Westerners increased dramatically, particularly for Satsuma, as Western ships frequently landed in the Ryukyus and sought not only trade, but formal diplomatic relations.
To increase his influence in the shogunate, Nariakira engineered a marriage between Shōgun Tokugawa Iesada and his adopted daughter, Atsu-hime (later Tenshō-in).

In 1854, the first year of Iesada's reign, Commodore Perry landed in Japan and forced an end to the isolation policy of the shogunate.
However, the treaties signed between Japan and the western powers, particularly the Harris Treaty of 1858, put Japan at a serious disadvantage.
In the same year, both Iesada and Nariakira died.
Nariakira named his nephew, Shimazu Tadayoshi, as his successor.
As Tadayoshi was still a child, his father, Shimazu Hisamitsu, effectively held the power in Satsuma.

Hisamitsu followed a policy of Kōbu gattai, or "unity between the shogunate and the imperial court".
The marriage between Tokugawa Iemochi, the next shōgun, and imperial princess Kazunomiya was a major success for this faction.
However, this put Satsuma at odds with the more radical Sonnō jōi, or "revere the Emperor and repel the barbarians" faction, with Chōshū as the major supporter.

In 1862, in the Namamugi Incident an Englishman was killed by retainers of Satsuma, leading to the bombardment of Kagoshima by the Royal Navy the following year.
Even though Satsuma was able to withstand the attack, this event showed how necessary it was for Japan to import western technology and reform its military.

Meanwhile, the focus of Japanese politics shifted to Kyoto, where the major struggles of the time occurred.
The shogunate entrusted Satsuma and Aizu with the protection of the Imperial court, against attempts of the Sonnō jōi faction to take over, as in the Kinmon Incident of 1864.
The shogunate decided to punish Chōshū for this event with the First Chōshū expedition, under the leadership of a Satsuma retainer, Saigō Takamori.
Saigō, however, avoided a military conflict and allowed Chōshū to resolve the issue with the Seppuku of the three perpetrators behind the attack on the Imperial palace.

When the shogunate decided to finally defeat Chōshū in a Second Chōshū expedition the next year, Satsuma, under the lead of Saigo Takamori and Ōkubo Toshimichi, decided to switch sides.
The Satchō Alliance between Satsuma and Chōshū was brokered by Sakamoto Ryōma from Tosa.

This second expedition ended in a disaster for the shogunate.
It was defeated on the battlefield, and Shōgun Iemochi died of illness in Osaka Castle.
The next shōgun, Tokugawa Yoshinobu, brokered a cease fire.

Despite attempts by the new shōgun to reform the government, he was unable to contain the growing movement to overthrow the shogunate led by Satsuma and Chōshū.
Even after he stepped down as shōgun and agreed to return the power to the Imperial court, the two sides finally clashed in the Battle of Toba–Fushimi 1868.
The shōgun, defeated, escaped to Edo.
Saigo Takamori then led his troops to Edo, where Tenshō-in was instrumental in the bloodless surrender of Edo castle.
The Boshin War continued until the last of the shogunate forces were defeated in 1869.
The Satsuma daimyō of the 1850s, Shimazu Nariakira, was very interested in Western thought and technology, and sought to open the country. At the time, contacts with Westerners increased dramatically, particularly for Satsuma, as Western ships frequently landed in the Ryukyus and sought not only trade, but formal diplomatic relations. To increase his influence in the shogunate, Nariakira engineered a marriage between Shōgun Tokugawa Iesada and his adopted daughter, Atsu-hime (later Tenshō-in).
In 1854, the first year of Iesada's reign, Commodore Perry landed in Japan and forced an end to the isolation policy of the shogunate. However, the treaties signed between Japan and the western powers, particularly the Harris Treaty of 1858, put Japan at a serious disadvantage. In the same year, both Iesada and Nariakira died. Nariakira named his nephew, Shimazu Tadayoshi, as his successor. As Tadayoshi was still a child, his father, Shimazu Hisamitsu, effectively held the power in Satsuma.
Hisamitsu followed a policy of Kōbu gattai, or "unity between the shogunate and the imperial court". The marriage between Tokugawa Iemochi, the next shōgun, and imperial princess Kazunomiya was a major success for this faction. However, this put Satsuma at odds with the more radical Sonnō jōi, or "revere the Emperor and repel the barbarians" faction, with Chōshū as the major supporter.
In 1862, in the Namamugi Incident an Englishman was killed by retainers of Satsuma, leading to the bombardment of Kagoshima by the Royal Navy the following year. Even though Satsuma was able to withstand the attack, this event showed how necessary it was for Japan to import western technology and reform its military.
Meanwhile, the focus of Japanese politics shifted to Kyoto, where the major struggles of the time occurred. The shogunate entrusted Satsuma and Aizu with the protection of the Imperial court, against attempts of the Sonnō jōi faction to take over, as in the Kinmon Incident of 1864. The shogunate decided to punish Chōshū for this event with the First Chōshū expedition, under the leadership of a Satsuma retainer, Saigō Takamori. Saigō, however, avoided a military conflict and allowed Chōshū to resolve the issue with the Seppuku of the three perpetrators behind the attack on the Imperial palace.
When the shogunate decided to finally defeat Chōshū in a Second Chōshū expedition the next year, Satsuma, under the lead of Saigo Takamori and Ōkubo Toshimichi, decided to switch sides. The Satchō Alliance between Satsuma and Chōshū was brokered by Sakamoto Ryōma from Tosa.
This second expedition ended in a disaster for the shogunate. It was defeated on the battlefield, and Shōgun Iemochi died of illness in Osaka Castle. The next shōgun, Tokugawa Yoshinobu, brokered a cease fire.
Despite attempts by the new shōgun to reform the government, he was unable to contain the growing movement to overthrow the shogunate led by Satsuma and Chōshū. Even after he stepped down as shōgun and agreed to return the power to the Imperial court, the two sides finally clashed in the Battle of Toba–Fushimi 1868. The shōgun, defeated, escaped to Edo. Saigo Takamori then led his troops to Edo, where Tenshō-in was instrumental in the bloodless surrender of Edo castle. The Boshin War continued until the last of the shogunate forces were defeated in 1869.
Satsuma Domain