The formation of the DIU signaled the start of the revolutionary cause of Juche in Korea.

Kim Il Sung began revolutionary activities in his early days, determined not to return to the homeland unless he liberated Korea from the Japanese colonial rule.

In June Juche 15 (1926), he entered Hwasong Uisuk School at the request of his father's friends. The school was founded by the Korean nationalists with a view to training cadets for the independence army.

During the school days, he had a new view of the nationalist movement. Regarding the nationalists' way of struggle as anachronistic, he tried to find out a new way.

While reading the Communist Manifesto and other revolutionary books, he studied the prevalent revolutionary principles in comparison with the Korean situation. At last, he came to have belief that Korea's revolution should be made to get the Japanese imperialists out of the country and build a new society in which popular masses enjoy wellbeing. He also came to have an idea that all affairs should be judged and settled in an independent way and popular masses should be awakened and aroused to the struggle for independence.

On the basis of this belief, he formed the DIU, a vanguard organization of young communists of new generation, advancing the immediate tasks and ultimate object of the Korean revolution.

Since then, the Korean revolution has taken to the road of independence.