Satsuma (薩摩国; -no Kuni) was an old province of Japan that is now the western half of present day Kagoshima prefecture on the island of Kyushu. Its abbreviation is Sasshū (薩州).
In 1871 with the abolition of feudal domains and the establishment of prefectures (Haihan Chiken) after the Meiji Restoration, the provinces of Satsuma and Osumi were combined to eventually establish Kagoshima prefecture.
Historically, the oligarchy that came into power after the "Meiji Restoration" of 1868 had a strong representation from the Satsuma province, as both Okubo Toshimichi and Saigo Takamori were from there.