Ryu, Gwan-Sun (March 15, 1902 – October 12, 1920) was a student and organizer in what would come to be known as the March 1st Movement against the Japanese colonial rule of Korea in South Chungcheong. In 1919, Yu, Kwan-Sun was a student at Ewha Womans University's high school in Seoul, where she witnessed the beginnings of the March 1st Movement. Her deep faith in God and the teachings from the Methodist Ehwa School gave her the courage to act boldly. When the school went into recess, following an order by the Japanese government closing all Korean schools, she returned to her home in Jiryeong-ri (now Yongdu-ri).
There, along with her family, she began to arouse public feeling against the Japanese occupation. She also planned a demonstration for independence, which included people from some neighboring towns, Yeongi, Chungju, and Jincheon. The demonstration was scheduled to start on the first lunar day of March 1919 at 9:00 a.m. in Awunae Marketplace. About 2,000 demonstrators shouted, "Long live Korean Independence!" ("대한독립만세"). The Japanese police were dispatched at around 1:00 p.m. that same day, and Yu was arrested with other demonstrators. Both her parents were killed by Japanese police during the demonstration.
Yu served a brief detention at Cheonan Japanese Military Police Station, and then she was tried and sentenced to seven years of imprisonment at Seodaemun Prison. During her sentence, Ryu, Gwan-Sun continued to protest for the independence of Korea, for which she received harsh beatings and torture. She died in prison on October 12, 1920, reportedly as the result of torture. Her final words were, "Even if my fingernails torn out, my nose and ears rip apart, and my legs and arms crush, the pain of losing my nation is more brutal."
The Japanese prison initially refused to release her body, but eventually and reluctantly the prison released her body to Lulu Frey and Jeannette Walter, principals of Ewha Womans School, and only after Frey and Walter threatened to expose this atrocity to the world. Her body was reported to have been cut into pieces. Contrary to this report, Walter, who dressed the body for burial, claimed that it had not been mutilated. The body was contained inside an oil crate which was supposed to be returned to Saucony Vacuum Company. The Japanese Authorities did this as a retaliation against the threat from Ehwa School.
She was posthumously awarded the Order of Independence Merit in 1962.