Answer:
The Tang Dynasty, which ruled China from 618 to 907 CE, conquered Vietnam, and made it the southernmost province of China.
Vietnam, up until that point, had been a problematic place for China, even it it was much smaller. The Tang Dynasty was able to conquer the area, and integrate into the central bureacuracy of the Empire, this is why they began to referred to Vietnam as the "pacified south".
Answer:
I guess you mean 30 year peace treaty?
The Thirty Years' Peace was a treaty, signed between the ancient Greek city-states Athens and Sparta, in the year 446 or 445 BCE.
More educated, wealthy, and urban than most Americans. shared same core ideas: people were self-interested, distribution of wealth was principal source of political conflict, main object of gov't was protecting private property, and that power should be set against power to balance gov't.