Question

What was the eventual outcome of the Vietnam War?

Answer 1

The victory of the North over the South and consequent reunification of the two parts under communist rule.

Explanation:

We can consider the term Vietnam War as representative of the conflict (started almost immediately after WWII and the liberation of the country from the Japanese occupation) between:
1) the Viet Minh of the North under the leadership of Ho Chi Minh against the French and their colonial army;
2) The North Vietnamese Army (NVA) and the Vietcong against the South pro-US governments and US backed army.

The first stage ended with the "liberation" of the North and the expulsion of the French from the northern part (see battle of Dien Bien Phu).
The second is more complex and saw a long and bitter war between the army of North Vietnam, supported by the guerilla warfare style of the Vietcong, against the army of the South and US force.

Subsequently the American forces withdrew from the fighting and from Vietnam trying to handle the continuation of the war, against the communists, to the South Vietnamese Army alone.

Finally, after few years, we had the collapse of the military/political structure of the South and the victory of the NVA (fall of Saigon, April 1975).

[NVA tank smashing through the gates of the presidential Palace in Saigon]
The result of the war was the reunification of the two Vietnams in one country under communist rule. The old capital of the South, Saigon, was renamed as Ho Chi Minh City.