Oh-Kwangsun sought asylum to China in 1917 following the teachings of his father's "Righteous Army" against imperial Japan and his hometown teacher, Yeo-jun. He joined Sinheung Military school in Seogando, China, where he became an instructor and an independent military official. He also led the Korean-Chinese coalition to the battlefield as the head of the Korean Independent Army.
As his mentor Yeo Jun passed away, he served as a official for the cultivation of the Independence Army along with Yi,Cheong-chun under the orders of President Kim-Gu of the Provisional Government of Korea. Furthermore, he infiltrated Beijing, an occupied area of the Japanese military, and was sentenced to prison for spying. After his country’s liberation, he served as the head of the Liberation Army's domestic zone to help the provisional government return to the country, and was a typical anti-Japanese and founding soldier who had served till his last rank of brigadier general while participated in the creation of the Korean military. Furthermore, his two children and his son-in-law worked hard on the independence movement. Indeed, he is a well-known family member who participated in the independence movement for three consecutive generations. Oh-Gwang-seon's life is dominated by the anti-Japanese independence movements and the construction of a liberated Korea. Not only did he participate in various battles at the forefront of the anti-Japanese independence war, but he also contributed to the creation of the Korean Armed Forces. His life in the construction of a liberated Korea must be the great root of today's Republic of Korea.