In 1905 Kim returned to Korea, teaching widely. He fled to China in 1913, following the Japanese annexation of Korea in 1910.
In 1919, unlike his contemporary Syngman Rhee, Kim successfully travelled to Paris for the Paris Peace Conference to lobby for Korean independence from Japan. He was sent by Lyuh Woon-Hyung and Chang Duk-soo, who had organized Sinhan Cheongnyeondang in Shanghai in the summer of 1919. His efforts in Paris proved to be futile since the United States, even though its president at the time Woodrow Wilson had championed the cause of national self-determination in his Fourteen Points, had no interest in upsetting its close ally Japan. He was a leading member of the Provisional Government of the Republic of Korea based in Shanghai, becoming the Vice-President.
After the liberation of Korea in 1945, he returned to his homeland to participate in the formation of a newly independent state, which was now under the rule of the United States Army Military Government in Korea in the south and the Soviet Civil Authority in the North. Kim was favored by the American occupation leader John R. Hodge, who saw him and Lyuh Woon-Hyung as moderate leaders on the right and left, respectively. In September 1947, the United States pushed to move the Korean question to the newly created United Nations, which quickly the voted to allow for elections in the south despite the objections of southern nationalists such as Kim and Kim Gu as well as from the north's Interim People's Committee, who were opposed because of the non-participation of the North. After failed efforts to broker reunification in that year, he retired from politics. After the outbreak of the Korean War in 1950, he was kidnapped and taken to the North; he reportedly died near Manpo in the far north on December 10.