The Korean response to independence from Japan at the end of WW2 was to form governments, beginning in August 1945. These largely consisted of People's Committees at the local level, and the Committee for the Preparation of Korean Independence (CPKI), planned as a provisional national government, in Seoul. The majority of the People's Committees were in the south, as one would expect from the majority of the population being in the south. The People's Committees were often leftist.

Superimposed on this was the military occupation of the Korea, with occupation north of the 38th parallel by the Soviet Union, and south of the 38th by the USA. The US response to the People's Committees and the CPKI was to dismantle the People's Committees and not recognise the authority of the CPKI. Instead, the US formed the United States Army Military Government in Korea (USAMGIK) which ran South Korea until the First Republic took over the reins of government. In the north, the Soviet Union allowed the People's Committee's to do their work, protected them from anti-leftist opposition, and formed the Soviet Civil Administration (SCA) to coordinate things nationally. The Soviets formed the Five-Province Administration in November 1945, led by Koreans, with Soviet Advisors included, and with the SCA operating in parallel. The Soviet Union also placed Red Army officers as advisors in the People's Comittees. In February 1946, the Soviet Union formed the Provisional People's Committee of North Korea as a Korean-run national provisional government, with the SCA reduced in role to an advisory body. The Soviets made sure that the province-level People's Committees and the PPCNK were communist-led, and mostly with a communist majority.

The Moscow Conference of 1945 (the Moscow Conference of Foreign Ministers of the United States, the United Kingdom, and the Soviet Union) had decided that (a) Korean self-government would be after a period of trusteeship of up to five years, and (b) a joint USA-USSR Joint Commission would plan for a single government of and independent united Korea. This decision was opposed by most Korean nationalists, who wanted an independent united Korea immediately. One nationalist leader who opposed the trusteeship was Cho Man-sik, who had been the leader of the Five-Province Administration. His opposition led to his removal from power, and the replacement of the Five-Province Administration by the PPCNK led by Kim Il-sung, communist and willing the support the Soviets on the trusteeship issue. His success in this position led to his future as the leader of communist North Korea (DPRK). The formation of the DPRK was a multi-step process, first with elections for the People's Committees up to and including the province level in November 1946, followed by elections (by the People's Committees) for the People's Assembly of North Korea, which then selected the People's Committee of North Korea (chaired by Kim Il-sung) which was the provisional government until the formation of the DPRK.

Provisional governments had a long history in Korea, with at least 6 being formed as a result of the March 1 Movement in 1919, which aimed, unsuccessfully, for independence from Japanese colonial rule. Before the end of 1919, the 6 main provisional governments combined to form the Provisional Government of the Republic of Korea, based in Shanghai, with Syngman Rhee as its president (Rhee had roles as President, Chancellor, and Foreign Minister in 3 of the 6 provisional governments). Rhee was impeached for corruption (a sign of the future?) in 1925, but continued to work for Korean independence.

Rhee was American-educated (included a PhD from Princeton in 1910), and a major figure in the Korean independence movement. Rhee became a major figure in south Korean affairs under USAMGIK. This included forming the Central Committee for the Rapid Realisation of Korean Independence, which with other organisations joining, became the political party called the National Association for the Rapid Realisation of Korean Independence. USAMGIK liked him because he spoke English fluently and had lived in the USA for decades. Having lived in the USA for decades, he had fewer recent enemies in Korean political circles than many. In addition, he was willing to go along with, and even push plans for, separate elections in the south, rather than insisting on Korea-wide elections for a unified independent Korea. Thus, he became president again of the Provisional Government of the Republic of Korea, now acting as trued provisional government for southern Korea. With the elections of a Constitutional Assembly in the south in May 1948, which proceeded to develop what became the consitution of the First Republic of South Korea, and elected the first president. Rhee's party, the National Association, was the largest party in the Constitutional Assembly, and other major leadership figures had left the party due to opposition to the separate elections in the south. This left Rhee well-placed to become the first president, and he indeed became the first president.

The rises of Kim Il-sung and Syngman Rhee had much in common. Both had well-established credentials in the Korean independence movement (Kim as a guerrilla and Rhee as a politician). Both were supported and liked by the occupying forces in their parts of the country, and both were willing to go along with the division of Korea (temporarily! - both sought reunification by force shortly afterwards), which led to them remaining as candidates for leadership while competitors fell by the wayside over opposition to division.

The actual governments both in the north and south were elected, with the occupiers of north and south ensuring that they were communist dominated and led, and anti-communist, respectively.