Keeping deep in mind his father's intention that a man born in Korea must know Korea well, Kim Il Sung crossed the River Amnok in his teens on March 16, Juche 12 (1923).

The journey from Badaogou of China to Mangyongdae of Korea was very long and difficult, but he felt painful seeing the tragic state of the motherland that was groaning under the colonial rule of the Japanese imperialists, and fostered the surging hatred against the Japanese imperialists and exploiters.

In his reminiscences "With the Century", the President said:

I had spent only two years back in my motherland, but I had learned and experienced much in those years. My most valuable experience was to have acquired a deep understanding of our people. Our people were simple, and industrious yet brave and strong-willed.

The President came to have a firmer belief that he could liberate the country from Japan's colonial rule if he organized the efforts of the people properly. And with this belief, he had waged the twenty years of anti-Japanese armed struggle relying on the popular masses to liberate the country.

He opened up the Juche-oriented path of the Korean revolution and built a powerful socialist country independent in politics, self-supporting in economy and self-reliant in defence, performing great feats on behalf of the country and history in his lifetime.