In 1950, as the international community was coming to terms with the aftermath of World War II, a new conflict broke out at the edge of the Asian continent.
It was a rare example of the Cold War turning hot - pitting the US and its allies against the USSR, North Korea and communist China. It was marked by dramatic swings of fortune and a devastating death toll.
Estimates vary, but at least two million Korean civilians, up to 1.5m communist forces, and around 30,000 US, 400,000 South Korean and 1,000 UK troops are believed to have died.
For two of the three years that the war was under way, both sides were actually trying to negotiate a peace.
When a ceasefire was eventually signed, on 27 July 1953, no-one could have guessed that 50 years later, the two Koreas would remain technically at war.
A peace treaty has never been signed, and the border continues to bristle with mines, artillery and hundreds of troops.