Communities with war industries experienced an immediate labor surplus when those industries closed down, and the large numbers of returning soldiers added to the unemployment problem.
I think the most important event was when the pilgrims came to the Americas. Although they came there to escape persecution, they were the first to start a colony and life there. Once that colonization started, many other European also wanted to come to the Americas to find more freedom and escape persecution.
To decide how laws are interpreted.
So the people can get water and there is fertile soil