The protests were triggered by the discovery of the body of a local high school student killed by police during demonstrations against rigged elections in March.

Popular discontent had arisen due to Rhee's autocratic rule, corruption, use of violence against political opposition, and uneven development of South Korea.

[2] Rhee resigned on April 26 before fleeing to exile in the United States, and was replaced by Yun Posun, beginning the transition to the Second Republic of South Korea.

Rhee faced increasing domestic discontent following the end of the Korean War in 1953, however, as his administration delivered limited economic and social development, while angering the public by amending the constitution to prolong his stay in power.

The South Korean public widely perceived Rhee as a corrupt and authoritarian leader who used autocratic methods to maintain his rule and cronyism in the government.

In 1959, Rhee was shocked and threatened when the United States reduced its economic aid to South Korea from a high of $382,893,000 in 1957 to $222,204,000, and began taking desperate measures to ensure his political survival.

In July 1959, Rhee accused Cho Bong-am of being a communist, and the Progressive Party leader was subsequently imprisoned and swiftly executed.

[5] Cho Pyong-ok went to the United States for a stomach operation at the Walter Reed Army Medical Center but died there of a heart attack.

Lee ran against the Democratic Party candidate Chang Myon, who had been South Korea's ambassador to the United States during the Korean War.

[3] On March 15, the same day as the election results, members of the Democratic Party in the southern city of Masan launched a protest against the electoral corruption.

Authorities announced that an autopsy confirmed that the cause of Kim's death was drowning, but many rejected this explanation and some protesters forced their way into the hospital where his body was kept.

Secretary of the Interior Choi In-Kyu, the official most responsible for the order, and Kwak Yong-ju, the Presidential security chief, who was also involved in the shootings, were both hanged at Seodaemun Prison on December 21, 1961.