People from the Eastern, such as slavic-speaking regions, and Southern European regions, such as Greece and Italy, made up the majority of immigrants from the 1890s to the 1920s. This marked a shift from the previous decades, in which Central and Northern European regions were sending the most immigrants to the United States.
The Mandate of Heaven was essentially a legitimization tool. By stating that their leadership was not just because they were selected or part of some royal family but instead because of divine choosing greatly strengthened their authority. For example, imagine the emperors before the Mandate of Heaven was established. Besides the obvious fact that they were emperor, there's no real reason that the people should follow their rules (at least no significantly convincing one). Now, on the other hand, the people believed that those rules and demands by their emperor were actually divine.
