The First Republic of Korea had existed since 1948 under President Syngman Rhee, who was widely considered to be a corrupt leader abused his presidential powers to maintain his rule and cronyism.

Although the First Republic was officially a representative democracy, Rhee adopted a strongly anti-communist position and used the threat of communism to enact a policy (such as the National Security Act) of severe repression against all political opposition, effectively assuming dictatorial powers.

Tolerance of Rhee and his Liberal Party-dominated government declined in the mid-to-late 1950s, as the South Korean public were increasingly discontent with the repression and the limited economic and social development.

[3][5] Under pressure from the left-wing, the Chang government carried out a series of purges of military and police officials who had been involved in anti-democratic activities or corruption during the First Republic.

[5] The government formulated a five-year economic plan based around agriculture and light industry to decrease unemployment, but was ultimately overthrown before having the chance to carry it up.

[5][7] Chang's government resumed negotiations for the normalization of Japan–Korea diplomatic relations, which had not progressed under the Rhee regime that had existed since the end of Japanese rule.

The lack of development under Rhee provoked a growing nationalistic intellectual reaction which called for a radical restructuring of society and a thorough political and economic reorganization, rejecting the model being pursued by the governing elite.

Park Chung Hee, a Major General in the Republic of Korea Army with decidedly ambiguous political leanings, was heavily influenced by this unfolding intellectual reaction.