Who: North and South Vietnam
What: The war was about the south and USA government. It was a Cold War. It started in November 1, 1955-April 30, 1975. Some major events are that the leader Ho Chi Minh declared all out war. The USA was helping the other side of the war. It was a 20 year war. Also no one won and it was the first war that USA lost.
Why: because USA was helping the other side.