Why is the seven years War describes as one of the most important wars in modern history?

Because it was the war that defined strength of the European forces, but also their distribution of force in the North America. It also led to decline of power of certain countries, such as France, that later collapsed into revolution.

Explanation:

Some historians are even arguing that this is the first world war, because it was led both in Europe, but also in colonies, where it was known as the French and Indian war. Although France was the greatest loser of the war, and it lost territories in North Africa, even the countries that were consider victorious such as Britain had many problems, mostly economical.

sumerians were responsible.