The Japanese invaded Korea in 1910 and made Seoul its colonial capital. The period of Japanese rule lasted until the end of World War II. After World War II the liberated Republic of Korea (South Korea) came into being with Seoul once again its capital. In 1950 the Korean War broke out and Seoul changed hands between the Chinese-backed North Korean forces and the UN-backed South Korean forces several times, leaving the city heavily damaged. In addition a great many refugees entered Seoul during the war, swelling its population to an estimated 2.5 million - more than half of them homeless.
In the post-war years Seoul was the focus of an immense reconstruction and modernization effort. Today the population of the Seoul area comprises 24% of the total population of South Korea and Seoul ranks seventh in the world in terms of the number of major companies based there. Seoul hosted the 1988 Summer Olympics and was one of the venues of the Football World Cup in 2002.
In 2004 the South Korean Government came up with a highly controversial plan to relocate the capital to the Gongju area in order to ease the population pressure on Seoul and set up the seat of government at a safer distance from North Korea. The plan was finally abandoned when judged unconstitutional by the courts without a nationwide referendum.