On June 25th, the Korean War began with a surprise invasion by around 80,000 North Korean troops. They faced a South Korean army of less than half as many men.
Within four days, South Korea’s capital city – Seoul – had been taken. Thus began a long and tortuous withdrawal by South Korean troops toward the southern port city of Pusan. The situation seemed hopeless until a daring amphibious assault in September of the same year created a barrier between the invading force in the south, and its supply chain that extended all the way from South Korea’s northern border: the 38th parallel. U.S. and South Korean forces chased the North Koreans across the border and beyond, eventually stopping at the Yalu River that formed the border between North Korea and China. The approach was close enough to provoke an invasion by around 400,000 Chinese nationals.
When a fragile cease fire was signed three years later, over 35,000 Americans lay dead. By contrast, over half a million North Korean and Chinese soldiers had been killed. (Estimates are as high as 58,000 U.S. deaths, and over a million Chinese and North Korean KIA.) The border remains in roughly the same location as it did when the war began.
To this day, U.S. troops continue to monitor the border. The peace is tense, and has not eased since hostilities ceased some 58 years ago. These two videos give a quick overview of the entire war.