How or why did the South African border war happen, who was involved and what was the outcome?
This was a long war that lasted from 1966 to 1989. One side of the war was the government of South Africa and its allies within Angola. The other side was the government of Angola and a group called SWAPO that was fighting for the independence of Namibia.
The war started because South Africa was trying to get official control over an area that is now called Namibia. South Africa had ruled this area since WWI and now wanted to officially have it be part of their country.
The outcome of the war was that Namibia became independent and the civil war within Angola got worse.