Answer 1:
The unification of civilizations had been observed in numerous place in history including China, the Mongolian plains and even in the Middle East and Egypt.
Explanation 1:
Most territories in the world was divided into small city states, kingdoms and even tribes. However, due to this disunity, they were never able to build up proper governance and improve trade and economics. Unification came about as a way to end wars, build alliances and have a powerful central government. All of which resulted in prosperity.
Answer 2:
This is due to the autocratic nature of the government and the need to legitimatize the rule of the King.
Explanation 2:
Without any democratic governments, a monarch always felt threatened, either from an uproar among the population, from of his own family members or advisers and invasion from another country.
In order to legitimatise his rule and give him some sense of authority, the king would closely work with priests and religious men and use a 'divine right of rule' as a way to justify his power. Civilians believed that the royal family did have sacred decree to run affairs of the government.
In some cases, e.g. the Pharaohs of Egypt, were believed to be god themselves.
Answer 3:
Peace in the area, a stable economy, education and better human rights always help.
Explanation 3:
Throughout history, we have seen that the best arts and sciences always developed in places with relative peace, good trading relations and an aristocracy that supports arts and crafts.
As ex example, lets look at 14th century Florence. The city had great trading relations with the Middle East and rest of Europe, giving rise to a wealthy upper class, that supported education and arts.