The Korean War began when North Korean Forces attacked the South Korea. North Korea being ruled by Communist government was given support from Russia and China, while South Korea was supported by US.
The Korean War
It is known as "forgotten war of 1950", because unlike World War 1, World War 2 which were given more focus by historians and media, this war was not given much focus by both. Around 5 million people lost their lives in this war.
As per the question, the answers are:
1. The Korean War began when North Korean Forces invaded in 1950.
2. The country labeled "A" is China. It entered on the side of North Korea.
3. The dividing line between North Korea and South Korea on the map is located close to the 38th parallel.
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