In 1950, conflict between North and South Korea threatened to explode into a much wider war. It became an international concern when the US supported the South Koreans, and the communist countries of China and the Soviet Union championed the North Koreans.
Truman Doctrine (1947)
US president Harry Truman announces that the US will seek to stop the spread of communism in places it had not spread to yet - a policy known as the "Truman Doctrine".
After World War II (1948)
The Korean peninsula was under Japanese rule before World War II. After Japan’s defeat in the war, the Soviet Union occupies the north of the country, while the US controls the south.
Korea is partitioned into two countries, but both communist North Korea and democratic South Korea hope to overthrow the other, and reunite the country.
North Korea invades (1950)
Communist North Korea strikes first and invades the South. The North makes great gains, and captures the South Korean capital, Seoul.
US and China join (1950)
Through the United Nations (UN), the US sends troops to help South Korea in July, turning the tide in the South’s favor. By October, they have driven the North back and have even taken the North’s capital city, Pyongyang. China enters the war to help the North.
China’s intervention drives the South Korean and UN troops south. A stalemate emerges, with each side’s territory reverting back to the prewar borders. Peace talks begin, but don’t achieve anything.
The two sides agree to a truce, which ends the fighting. The border between the two countries stays where it was before the war, and a demilitarized zone is set up between them.
The Geneva talks (1954)
The US and China meet to talk about uniting the two Koreas, but they can’t reach an agreement. The Korean peninsula remains divided to this day - with a communist North and a democratic South.
Refugees: The back-and-forth nature of the war creates a huge refugee crisis as people flee to find safety. By 1951, about 500,000 refugees crowded into the South Korean city of Busan, with the overall number of refugees created by the war believed to be between four and six million.