The history of the Workers' Party of Korea (WPK) encompasses the period from 1949 onwards.
Founding
According to North Korean sources, the origins of the Workers' Party of Korea can be traced to the Down-with-Imperialism Union, which was supposedly founded on October 17, 1926 and led by Kim Il Sung, then 14 years old. It is described in these sources as "the first genuine revolutionary communist organization in Korea."Kim Il-sung. Works Vol. I. Pyongyang: Foreign Languages Publishing House. 1980. p. 467. The Workers' Party of North Korea was formed on 29 August 1946 from a merger between the Communist Party of North Korea and the New People's Party of Korea (조선신민당).Kim Il-sung. Works Vol. 2. Pyongyang: Foreign Languages Publishing House. 1980. p. 327.
On June 24, 1949, the Workers Party of North Korea and the Workers' Party of South Korea merged, forming the Workers' Party of Korea, at a congress in Pyongyang. Both parties traced their origins to the Communist Party of Korea. Kim Il Sung of the Workers Party of North Korea became the party Chairman and Pak Hon-yong, who had been leader of the Workers Party of South Korea as well as the earlier Communist Party of Korea, and Ho Ka-i, . becoming deputy chairmen. There were a total of ten members of the first DPRK Politburo. The other members were Yi Sung-yop, Kim Sam-yong, Kim Chaek, Kim Tu-bong, Pak Il-u, and Pak Chong-ae. Most were later purged by Kim Il Sung.
However, official North Korean sources consider October 10, 1945 as the 'Party Foundation Day', citing a founding meeting of the 'North Korea Bureau of the Communist Party of Korea' founded under Soviet guidance. Foreign historians, however, dispute that date and claim that the meeting was in fact held on October 13. The party considers itself as a direct continuation of the North Korea Bureau and the Workers Party of North Korea, considering the two congresses of the Workers Party of North Korea as its own. This version of events can be seen as a move to downplay the importance of the communists from South Korea, who were purged in the 1950s.
The first five years of the WPK's rule were dominated by the Korean War. By October 1950, United Nations forces had occupied most of the DPRK and the WPK leadership had to flee to China. Many believe that if it had not been for Chinese intervention, the Korean communists would have been militarily defeated at that point. But in November, Chinese forces entered the war and threw the U.N. forces back, retaking Pyongyang in December and Seoul in January 1951. In March U.N. forces retook Seoul, and the front was stabilised along what eventually became the permanent "Armistice Line" of 1953. The WPK was able to re-establish its rule north of this line.
Education of new state apparatus In preparing to build the party-state according to the tradition in other states of the communist bloc, Kim Il Sung quoted Joseph Stalin's statement that "cadres decide everything", and thrust the cadre policy into the forefront of issues needing attention.Sheila Fitzpatrick, "The Cultural Front: Power and Culture in Revolutionary Russia" The first problem was that trained workers were in extraordinarily short supply. Kim himself realized the severity of this problem, saying in June 1946 that "If we have about 500 trained cadres, then we can dispatch one hundred to each of the five provinces to solve the shortage problem. But, we do not have such trained cadres".Kim Il sung, "The Central Party School is a Communist University for the Education of Party Cadres, June 3, 1946", in "Collected Works of Kim Il-sung", 1979.
Accordingly, he started to establish schools for the educating of bureaucrats who would be appointed to the party military and cabinet. In February 1946, Pyongyang Institute opened its doors to students who would soon become relatively high-ranking military leaders, and three months later, the Training Institute for Security Officers and the Central Party School began educating military officers and party cadres respectively.Kim Il-sung 's military thought, Institute for North Korean Studies, Seoul, 1978, p.223
Factions As the Workers' Party of Korea, and its two founding parties, had emerged through a series of mergers, it contained various competing factions. At the time of its foundation, the party was made up of four factions, the Soviet Koreans faction, the Domestic faction, the Yanan (or Chinese) faction and the Guerrilla faction. The Soviet Koreans, led first by Alexei Ivanovich Hegay and then by Pak Chang Ok were made up of waves of ethnic Koreans who were born or raised in Russia after their families moved there starting in the 1870s. Some of them had returned to Korea covertly as Communist operatives in the twenties and thirties but most were members of the Red Army or civilians who were stationed in North Korea following World War II to help the Red Army establish a Soviet satellite. Many came as translators or as Russian language instructors. The Domestic faction, led by Pak Hon-yong were Korean Communists who never left the country but engaged in a struggle against the Japanese occupation. Many members of the domestic faction had spent time in Japanese military prisons as a result of their activities. They were the ones who agitated that the Korean People's Army take the lead in national reunification through military means. The Yanan faction, led first by Mu Chong and then by Kim Tu-bong and Choe Chang-ik, were those Korean exiles who had lived in China's Shaanxi province and joined the Chinese Communist Party whose regional headquarters were at Yan'an. They had formed their own party, the North-Chinese League for the Independence of Korea, and when they returned to North Korea from exile they formed the New People's Party which merged with the North Korean Bureau to form the Workers Party of North Korea. Many members of the Yanan faction had fought in the Chinese 8th and New 4th Armies and thus had close relations with Mao Zedong. The Guerrilla faction, led by Kim Il Sung, was made up of former Korean guerillas who had been active in Manchuria after it was occupied by Japan in 1931. Many in this group ended up fleeing Manchuria, as their armed resistance was suppressed, and moved to the Soviet Union where many of them, including Kim, were drafted into the Red Army.
Once the WPK was created there was a virtual parity between the four factions with the Yanan, Soviet and Domestic factions each having four representatives on the Politburo with the Guerrilla faction having three.
In the early years of the party, Kim Il Sung was the acknowledged leader, but he did not yet have absolute power, since it was necessary to balance off the interests of the various factions. To eliminate any threats to his position, he first moved against individual leaders who were potential rivals. He drove from power Alexei Ivanovich Hegay (also known as Hŏ Ka-i), leader of the Soviet faction, first demoting him during the Korean War in 1951 and then using him as a scapegoat for slow repairs of a water reservoir bombed by the Americans to drive him from power (and to an alleged suicide) in 1953. In part, it was possible for Kim to do this because the intervention of "Chinese People's Volunteers" in the war reduced the influence of both the USSR and the Soviet faction and allowed Kim Il Sung the room he needed to dispose of his main rival.
Kim Il Sung also attacked the leadership of the Yanan faction. When the North Koreans were driven to the Chinese border, Kim Il Sung needed a scapegoat to explain the military disaster and blamed Mu Chong, a leader of the Yanan faction and also a leader of the North Korean military. Mu Chong and a number of other military leaders were expelled from the party and Mu was forced to return to China where he spent the rest of his life. Kim Il Sung also removed Pak Il-u, the Minister of the Interior and reputedly the personal representative of Mao Zedong.
The sacking of Hegay, Mu and Pak reduced the influence of the Chinese and Soviet factions, but Kim Il Sung could not yet launch an all-out assault on these factions because he would risk the intervention of Moscow and Beijing when he was still dependent on their support.
Purge of the "Domestic faction" As the Korean War drew to a close, Kim Il Sung first moved against the Domestic faction. While the Soviet faction had the sponsorship of the Soviet Union, and the Yanan faction was backed by China, the Domestic faction had no external sponsor who would come to their aid, and was therefore in the weakest position. With the end of the Korean War, the usefulness of the Domestic faction in running guerilla and spy networks in South Korea came to an end. Former leaders of the Workers Party of South Korea were attacked at a December 1952 Central Committee meeting. In early 1953, rumours were spread that the "southerners" had been planning a coup. This led to the arrest and removal from power of Pak Hon-yong (who was foreign minister at the time) and Yi Sung Yop the minister of "state control" who was charged with "spying on behalf of the United States". In August 1953, following the signing of the armistice that suspended the Korean War, Yi and eleven other leaders of the domestic faction were subjected to a show trial on charges of planning a military coup and sentenced to death. In 1955, Pak Hon-yong, the former leader of the WPSK and deputy chairman of the WPK, was put on trial on charges of having been a US agent since 1939, sabotage, assassination, and planning a coup. He was sentenced to death, although it is unclear if he was shot immediately or if his execution occurred some time in 1956.
The trials of Yi and Pak were accompanied by the arrest of other members and activists of the former SWPK, with defendants being executed or sent to forced labour in the countryside. The domestic faction was virtually wiped out, though a few individual members who had personally allied themselves to Kim Il Sung remained in positions of influence for several more years.
The "August incident" and aftermath
Kim Il Sung sent out preliminary signals in late 1955 and early 1956 that he was preparing to move against the Yanan and Soviet factions. The Twentieth Party Congress of the Soviet Communist Party was a bombshell with Nikita Khrushchev's Secret Speech denouncing Joseph Stalin and the inauguration of destalinisation. Throughout the Soviet bloc domestic Communist parties inaugurated campaigns against personality cults and the general secretaries who modelled themselves after Stalin were deposed throughout Eastern Europe.
Kim Il Sung was summoned to Moscow for six weeks in the summer of 1956 in order to receive a dressing down from Khrushchev, who wished to bring North Korea in line with the new orthodoxy. During Kim Il Sung's absence, Pak Chang Ok (the new leader of the Soviet faction after the suicide of Ho Ka Ai), Choe Chang Ik, and other leading members of the Yanan faction devised a plan to attack Kim Il Sung at the next plenum of the Central Committee and criticise him for not "correcting" his leadership methods, developing a personality cult, distorting the "Leninist principle of collective leadership" his "distortions of socialist legality" (i.e. using arbitrary arrest and executions) and use other Khrushchev-era criticisms of Stalinism against Kim Il Sung's leadership.