Japan tried to suppress Korean traditions and culture and ran the economy primarily for its own benefit. Anti-Japanese, pro-liberation rallies took place nationwide on 1 March 1919 (the March 1st Movement). About 7,000 people were killed during the suppression of this movement. Continued anti-Japanese uprisings, such as the nationwide uprising of students in 1929, led to the strengthening of military rule in 1931. After the outbreaks of the Sino-Japanese War in 1937 and World War II, Japan stepped up efforts to extinguish Korean culture.
Koreans were forced to adopt Japanese names. Worship at Japanese Shinto shrines was made compulsory. The school curriculum was radically modified to eliminate teaching in the Korean language and history. Numerous Korean cultural artifacts were destroyed or taken to Japan. Resistance groups known as Dongnipgun (Liberation Army) operated along the Sino-Korean border, fighting guerrilla warfare against Japanese forces. Some of them took part in allied action in China and parts of South East Asia. One of the guerrilla leaders was the communist Kim Il-sung, who later became the leader of North Korea.
During World War II, Koreans at home were forced to support the Japanese war effort. Tens of thousands of men were conscripted into Japan's military. Around 200,000 girls and women, many from Korea, were forced to engage in sexual services for the Japanese military, with the euphemism "comfort women".
At the end of World War II in 1945, the Korean Peninsula was divided into two zones along the 38th parallel, with the northern half of the peninsula occupied by the Soviet Union and the southern half by the United States. Initial hopes for a unified, independent Korea evaporated as the politics of the Cold War resulted in the establishment of two separate states with diametrically opposed political, economic, and social systems.
Soviet general Terentii Shtykov recommended the establishment of the Soviet Civil Authority in October 1945, and supported Kim Il-sung as chairman of the Provisional People's Committee for North Korea, established in February 1946. During the provisional government, Shtykov's chief accomplishment was a sweeping land reform program that broke North Korea's stratified class system. Landlords and Japanese collaborators fled to the South, where there was no land reform and sporadic unrest. Shtykov nationalized key industries and led the Soviet delegation to talks on the future of Korea in Moscow and Seoul.
In September 1946, South Korean citizens had risen up against the Allied Military Government. In April 1948, an uprising of the Jeju islanders was violently crushed. The South declared its statehood in May 1948 and two months later the ardent anti-communist Syngman Rhee became its ruler. The Democratic People's Republic of Korea was established in the North on 9 September 1948. Shtykov served as the first Soviet ambassador, while Kim Il-sung became premier.
Soviet forces withdrew from the North in 1948 and most American forces withdrew from the South the following year. Ambassador Shtykov suspected Rhee was planning to invade the North, and was sympathetic to Kim's goal of Korean unification under socialism. The two successfully lobbied Joseph Stalin to support a short blitzkrieg of the South, which culminated in the outbreak of the Korean War.
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