History of South Korea
On August 15, 1948, the Republic of Korea was formally established, with Rhee Syngman as the first president. With the establishment of Rhee's government, de jure sovereignty also passed into the new government. On September 9, 1948, a communist regime, the Democratic People's Republic of Korea (North Korea), was proclaimed under Kim Il-sung. However, on December 12, 1948, by its resolution 195 in the Third General Assembly, the United Nations recognized the Republic of Korea as the sole legal government of Korea.
South Korea–Taiwan relations
The People's Republic of China (PRC) was founded in 1949 following the Chinese Civil War and Republic of Korea maintained relations with the Republic of China (ROC), whose government relocated to Taiwan. The United Nations condemned North Korea's military aggression against Republic of Korea in United Nations Security Council Resolution 82 and United Nations Security Council Resolution 84. The ROC voted in favor of both United Nations resolutions. During the Korean War, the ROC supplied material aid to ROK, while the People's Republic of China gave North Korea combatants to support the People's Volunteer Army.