In 1916, he became the vice principal of the , which Kim had taken over, in Seoul. He later became its principal. In 1918, Song and several others began plotting an uprising against the Japanese colonial government. After the
March 1st Movement protests of 1919, Song was arrested and held at
Seodaemun Prison. He spent a year and a half in prison, until he was acquitted of all charges and released around October 1920. After the beginning of the
Pacific War, on 8 December 1941, the Governor-General began conscripting Korean students to fight in the war. Frustrated by his inability to speak out against this, Song privately wrote that "
The Dong-a Ilbo is my mouth, my ears, my breathing nose, my hands, and my feet. How can a man with all of those parts sliced off do anything!"
After the liberation of Korea After the
liberation of Korea, the office of the Governor-General began planning its departure and hand off of control to Korean institutions. The security office had three Korean candidates that they felt who could handle their work: Song,
Lyuh Woon-hyung, and
Ahn Chai-hong. In mid-August, the head of security reached out to Song and offered him the position, which came with control over newspapers, broadcasting, transportation, and security. Song refused it. Associates of Song, such as , questioned the wisdom of the decision. According to historian , Song viewed the position as being akin to the role of
Wang Jingwei in the
Japanese puppet state. The position was then offered to Lyuh, who accepted it. Lyuh founded the
Committee for the Preparation of Korean Independence (CPKI). Lyuh asked Song on a number of occasions to join, but Song refused. On one occasion, their disagreements escalated into a shouting match. To counter the CPKI, Song became the founding leader of the (NFPC) on 7 September and the
Korea Democratic Party on 16 September. In December of that year, the
Moscow Conference was held. Afterwards, the United States and Soviet Union announced that they had failed to negotiate the reunification of Korea and that the peninsula would be occupied for 5 years. This roused up the . On the evening of 29 December, Song and members of the
Korean Provisional Government held a furious meeting on the results of the conference. ==Death==