Apart from two years in Korea during middle school, he spent most of his teenage years in China, a refuge and base for independence fighters like his parents. It was there, Kim recalls, that he began his self-study of communism, including Lenin's biography, at age 13. At 14, he joined a military academy in Jilin, where he began to get involved in the anti-Japanese movement.
In his memoirs, he recalls what he describes as a momentous gathering in a bare room in Oct. 17, 1926, when he and his friends created the Down-with-Imperialism Union, and elected him president. Kim says he considers that organization the root of the current ruling Workers' Party of Korea.
Even then, Kim knew the power of cloaking a political message in a good story. He recounts setting up a secret library and luring in classmates with love stories before slipping them books about communism.
By 1927, he writes, activists had decided to make Mount Paektu their base. In 1929, at age 17, Kim was thrown into jail. He says in his memoirs that he used the time to plot an armed Korean revolution.
When he was released the following May, he began recruiting members to join a new, communist political party, according to his official biography. North Korea now considers his founding of the Anti-Japanese People's Guerrilla Army on April 25, 1932, as the start of the modern-day Korean People's Army.
Kim also started going by the nom de guerre "Kim Il Sung," meaning "Kim, the sun." Kim wasn't the first warrior to pick that name — there were 16 well-known "Kim Il Sungs" in the previous decade with a reputation as fierce fighters, historian Song said.
The name marks the beginning of his bid to build for himself an aura of primacy. In later years, he became known as the "Sun," borrowing the potent symbol of power common to many religions and traditions. His April 15 birthday is called "Day of the Sun."
Kim's biography says he set up his guerrilla base in Manchuria in the early 1930s, and sought to push across the border by establishing headquarters at Mount Paektu by 1936. However, some experts say it is not clear whether he ever lived at Mount Paektu, and Song notes that Kim more likely served with communist Chinese forces rather than leading an independent guerrilla army.
Densely forested Paektu, straddling the Korean-Chinese border, was both a strategic defensive choice and a savvy symbolic one. Mount Paektu is Korea's highest peak and its most volatile, with an active volcano that still threatens to erupt. It's where Korea's first founder, the mythical Tangun, is said to have descended 5,000 years ago.
In the early 1940s, Kim was back in Manchuria and made forays back to the secret camp at Mount Paektu, according to his official biography. A month after Japan's defeat in August 1945, he sailed back to Korea with the Soviet army, clad in a Soviet military uniform, according to most accounts. He was 33.
As the Soviets and Americans divided trusteeship of newly liberated Korea along the 38th parallel, Soviet-backed Kim stepped into the void left by the end of Japanese colonial rule. When Seoul held its own separate elections in 1948, a new nation sprang up in the north that September: the Democratic People's Republic of Korea, with Kim as head of state.
During his career, Kim created and served in every top title in North Korea: premier, chairman of the Central Military Commission, supreme commander of the army, general secretary of the Central Committee of the Workers' Party and finally, president. Schooling, medical care and housing were all free. But in return he demanded filial, near-religious loyalty and an adherence to the militaristic rules that govern life in North Korea.
Defectors say those who oppose the party and state face imprisonment. Amnesty International estimates as many as 200,000 people are being held in North Korean labor camps today, based on satellite imagery and defector accounts. North Korea denies the existence of such gulags.
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