The first Republic of Korea was the government of South Korea from August 1948 to April 1960. The first republic was founded on 15 August 1948 after the transfer from the United States Army Military Government that governed South Korea since the end of Japanese rule in 1945, becoming the first independent republican government in Korea. Syngman Rhee became the first president of South Korea following the May 1948 general election, and the National Assembly in Seoul promulgated South Korea's first constitution in July, establishing a presidential system of government. The first republic claimed sovereignty over all of Korea but only controlled Korea south of the 38th parallel until the end of the Korean War in 1953, when the border was modified. The first republic was characterized by Rhee's authoritarianism and corruption, limited economic development, strong anti-communism, and by the late 1950s growing political instability and public opposition to Rhee. The April Revolution in April 1960 led to Rhee's resignation and the transition to the second Republic of Korea. Politics Rhee was supported in the elections by the Korea Democratic Party, but didn't include any of its members in his cabinet. In retaliation, the members of the party formed a united opposition Democratic Nationalist Party, and began to advocate a cabinet system which would remove power from the president. This led to a regrouping of the Rhee faction into the Nationalist Party, which later became the Liberal Party, and remained Rhee's base throughout his administration. The country's second parliamentary elections were held on May 30, 1950, and gave the majority of seats to independents. The South Korean government continued many of the practices of the U.S. military government. This included the brutal repression of leftist activity. The Rhee government continued the harsh military action against the Jeju Uprising. It also crushed military uprisings in Suncheon and Yeosu, which were provoked by orders to sail to Jeju and participate in the crackdown. Prewar This government oversaw several prewar massacres, the most notable being the Bodo League massacre where between 100,000 and 1,140,000 were executed on suspicion of supporting communism. Korean War On June 25, 1950, North Korean forces invaded South Korea, starting the Korean War. Led by the United States, a 16-member coalition undertook the first collective action under the umbrella of the U.N. Command (UNC). Oscillating battle lines inflicted a high number of civilian casualties and wrought immense destruction. With