Japan's 35-year rule in Korea ended after the Second World War
Consequently, the Democratic People’s Republic of Korea, a Soviet-style socialist republic, was established in the north while the Republic of Korea, a Western-style regime, was established in the South.
The conflict arose because both sides claim to be the government of the entire peninsula and during the Cold War, North Korea was backed by the Soviet Union, China and other communist states, while South Korea was backed by the United States and its allies.
Tensions erupted in what became the Korean War when on June 25, 1950 North Korea invaded the South using Soviet tanks and heavy artillery.
The South Korean forces had no equivalent weaponry to resist an attack and within five days were routed and the South Korean capital of Seoul had fallen.
The US had not anticipated the invasion and deployed troops in early July and what was left of the South Korean Army was placed under US operational command.
The UK sent 100,000 troops to fight alongside the Americans. During the war the British lost 1,078 killed and more than 1,000 captured by the enemy.
Many were tortured before their release.
The war, which lasted until 1953 cost the lives of more than 1½million people and fighting throughout the whole peninsula effectively destroyed most cities.
Though fighting ended in an armistice, officially the two governments remain at war.
Over the years the North and South continued a military standoff, with periodic clashes.
The conflict even survived the collapse of the Eastern Bloc of 1989 to 1991 and in 1997 President Bill Clinton described the division of Korea as the “Cold War’s last divide”.
In 2002, President George W. Bush described North Korea as a member of the “axis of evil” of America’s enemies along with Iran and Iraq.
In a historic summit in April, North Korea’s Kim Jong-Un and South Korea’s leader Moon Jae-in met on the south side of the Korean Demilitarised Zone at Panmunjom or Truce Village and agreed to work together to end the Korean conflict and improve relations between the two countries.
Their official declaration also included a commitment to the denuclearisation of the whole peninsula.
It was the first time since 1953 that a North Korean leader had entered the South’s territory; President Moon also briefly crossed into the North’s territory.
The summit took place after the two sides held several meetings in preparation for the joint attendance at the 2018 Winter Olympics held in PyeongChang in the South in February.