Proclamation of the Second Republic of Korea. From right: Chang Myon
(Prime Minister), Yun Bo-seon
(President), Paik Nak-jun (President of the House of Councillors) and Kwak Sang-hoon (President of the Chamber of Deputies).
The First Republic was overthrown by widespread protests known as the "April Revolution" in April 1960. After its fall, power was briefly held by an interim administration under  A new parliamentary election was held on 29 July 1960. The Democratic Party, which had been in the opposition during the First Republic, easily gained power and the Second Republic was established.
The Second Republic operated under a parliamentary system. This was the first and the only instance South Korea turned to a cabinet system instead of a presidential system. The legislature was bicameral, with the National Assembly as the lower house and the House of Councilors as the upper house. The president was elected by both houses of the legislature and served as head of state. Due to the numerous abuses of power by South Korea's first president, Syngman Rhee, the president's role was greatly reduced by the new constitution, to a point almost entirely ceremonial. Real power rested with the prime minister and cabinet, who were elected by the National Assembly. Yun Po Sun was elected as the President on 13 August 1960. The prime minister and head of government was Chang Myon.