Before Japanese rule Following Joseon's forced opening, Japan continued to open more and more parts of Korea to exclusive Japanese trade, to the chagrin of the citizens of Joseon as well as Joseon and Qing officials. In some areas of Korea and especially near the port of
Wonsan, "small roving bands of Koreans" attacked Japanese people who ventured outside at night. In 1882, the
Imo Incident occurred, in which general anti-foreigner sentiment (especially anti-Japanese) amongst the
Joseon Army and later the general citizenry led to the killing of both Korean government officials and members of the Japanese legation. In 1894, the
Donghak Peasant Rebellion occurred. Like the Imo Incident, this rebellion was also generally anti-foreigner, with a focus on Japan. This incident is what sparked the First Sino–Japanese War. In April 1896,
Soh Jaipil and others established the
Independence Club: the first political organization that advocated for Korean independence. Among other goals, the group advocated for the establishment of a
constitutional monarchy. While Gojong initially recognized and tolerated the organization, he eventually disbanded it in December 1898. Between 1905 and 1912, a number of volunteer guerrilla armies, called "
righteous armies" emerged among the Korean populace to fight the Japanese. Around 20,000 volunteers died in these confrontations, which ultimately did not stop the colonization of Korea.
Under Japanese rule in the aftermath of the March 1st Movement (1919)The period of Japanese colonial rule that ensued was oppressive to a far-reaching degree, giving rise to many Korean
resistance movements. By 1919 these became nationwide, marked by what became known as the
March First Movement. Japanese rule was oppressive but changed over time. Initially, there was very harsh repression in the decade following annexation. Japan's rule was markedly different than in its other colony,
Formosa. This period is referred to as
amhukki (the dark period) in Korean historiography and common parlance in Korea. Tens of thousands of Koreans were arrested by the Japanese colonial administration for political reasons. The harshness of Japanese rule increased support for the Korean independence movement. Many Koreans left the Korean Peninsula for Manchuria and
Primorsky Krai in Russia, some of whom formed resistance groups and societies in
Manchuria to fight for Korean independence. Koreans also carried out armed struggles against Japanese forces in Manchuria and Korea. In 1919 and 1920s, Korean independence army units engaged in resistance activities in Manchuria, which traveled across the Korean-Chinese border, using
guerrilla warfare to fight against the Japanese army. At this time,
Beom-do Hong's unit ambushed and annihilated the Imperial Japanese Army that was advancing in
Bongodong (Fengwudong),
Jilin,
Manchuria (June
1920). Also, the combined forces of the independence army commanded by
Jwa-jin Kim and Beom-do Hong, while repeatedly retreating operationally, ambushed and killed about 1,500 Imperial Japanese soldiers in
Cheongsanri (Qīngshānlǐ),
Jílín,
Manchuria. In retaliation to loss at
Battle of Qingshanli, the
Imperial Japanese Army committed the
Gando Massacre, massacring between 5,000 and tens of thousands of Korean civilians in
Gando. Some Koreans went to Japan, where groups agitated clandestinely. There was a prominent group of Korean Communists in Japan, who were in danger for their political activities. After the
Peace Preservation Law of 1925, some freedoms were restricted. Then, in the lead up to the invasion of China and World War II, the harshness of Japanese rule increased again.
Involvement in World War II Although the Empire of Japan had
invaded and occupied northeast China from 1931, the
Nationalist government of China avoided declaring war on Japan until the empire
directly attacked Beijing in 1937, sparking the
Second Sino-Japanese War. After the United States
declared war on Japan in 1941, China became an
Ally of World War II, and tried to exercise its influence within the group to support
Pan-Asian and nationalist movements, which included stipulating a demand of the complete surrender of Japan and immediate independence of Korea afterwards. In 1937, the
Korean National Revolutionary Party and other groups which had been campaigning for independence in China had a joint meeting in
Wuhan and established the left-wing (KNF). The
Korean Volunteer Corps was formed as an armed force under it. The Korean Volunteer Corps, with
Kim Won-bong as its commander-in-chief, was commanded by the Chinese
Military Affairs Commission, headed by
Chiang Kai-shek, according to the
national-communist cooperation. The Korean Volunteer Corps' co-founder was Japanese Anti-War activist
Kazuo Aoyama. In addition, Aoyama had served as the Corps' political advisor. Meanwhile, China tried to promote the legitimacy of the
Provisional Government of Korea (KPG), which was established by
Korean exiles in China after the suppression of the March 1st Movement in Korea. KPG was ideologically aligned with the Chinese government of the time, as independence leader
Kim Ku had agreed to Chiang Kai-shek's suggestion to adopt the Chinese
Three Principles of the People program in exchange for financial aid. The Chinese
Nationalist government in
Chongqing tried to unify the warring Korean factions, including the
Korean Liberation Army under KPG and the Korean Volunteer Corps under KNF; moreover, Chinese
National Military Council decided that "complete independence" for Korea was China's fundamental Korean policy. Although Chiang and Korean leaders like
Syngman Rhee tried to influence the
U.S. State Department to support Korean independence and recognize the KPG, the Far Eastern Division was skeptical. Its argument was that the
Korean people "were emasculated politically" after decades of Japanese rule, and showed too much disunity, preferring a
condominium solution for Korea that involved the Soviets. China was adamantly opposed to Soviet influence in Korea after hearing about
atrocities in Poland following its
Soviet takeover in 1939. By the
Cairo Conference, the US and China came to agree on Korean independence "in due course", with China still pressing for immediate recognition of the exile government and a tangible date for independence. After Soviet-American relations deteriorated, on August 10, 1945, the
United States Department of War agreed that China should land troops in
Pusan, Korea from which to prevent a Soviet takeover. However, this turnaround was too late to prevent the
division of Korea, as the
Red Army quickly
occupied northern Korea that same month. ==Ideologies and concerns==