Sakamoto Ryoma was a prominent Japanese samurai and political figure during the late Edo period. Born in 1836, he played a crucial role in the movement to overthrow the Tokugawa shogunate and modernize Japan. Ryoma was known for his vision of a unified Japan and his efforts to promote democracy and equality. He was instrumental in forming the Satcho Alliance, which united the domains of Satsuma and Choshu against the shogunate. Ryoma's life was cut short when he was assassinated in 1867, but his legacy continues to influence Japan's modernization and democratic development.