Vietnam was united, while Korea remained divided.
Vietnam finally reunited after the Vietnamese civil war on July 2nd, 1976.
Both North and South Korean leaderships have claimed that they will reunify Korea in the future, but little progress has been made.
Answer: vassals.
Explanation: A king (or lord) ruled large areas of land. To protect his land from invasion, the king gave parts of it to local lords, who were called vassals.
