The history of South Korea formally begins with its establishment on 15 August 1948, although Syngman Rhee had declared the establishment in Seoul on 13 August.
In the aftermath of the Japanese occupation of Korea which ended with Japan's defeat in World War II in 1945, Korea was divided at the 38th parallel north in accordance with a United Nations arrangement, to be administered by the Soviet Union in the north and the United States in the south. The Soviets and Americans were unable to agree on the implementation of Joint Trusteeship over Korea. This led in 1948 to the establishment of two separate governments, each claiming to be the legitimate government of all of Korea. Eventually, following the Korean War, the two separate governments stabilized into the existing political entities of North and South Korea.
South Korea's subsequent history is marked by alternating periods of democratic and autocratic rule. Civilian governments are conventionally numbered from the First Republic of Syngman Rhee to the contemporary Sixth Republic. The First Republic, arguably democratic at its inception, became increasingly autocratic until its collapse in 1960. The Second Republic was strongly democratic, but was overthrown in less than a year and replaced by an autocratic military regime. The Third, Fourth, and Fifth Republics were nominally democratic, but are widely regarded as the continuation of military rule. With the Sixth Republic, the country has gradually stabilized into a liberal democracy.
Since its inception, South Korea has seen substantial development in education, economy, and culture. Since the 1960s, the country has developed from one of Asia's poorest to one of the world's wealthiest nations. Education, particularly at the tertiary level, has expanded dramatically. It is said to be one of the "Four Tigers" of rising Asian states along with Singapore, Taiwan and Hong Kong.