<span>This question can refer to either first or second World Wars. In both cases it happened that 1) the immigrans and refugees went to other countries - such as Latin America, which affected those countries 2) almost all countries were affiliated with one or the other side - sending them ams for example 3) many other countries send their men to fight in those wars, which is why many Canadians and US-Americans fought and died in Europe</span>
You can check other sources as well
Article I, Section 4, Clause 1: The Times, Places and Manner of holding Elections for Senators and Representatives, shall be prescribed in each State by the Legislature thereof; but the Congress may at any time by Law make or alter such Regulations, except as to the Places of chusing Senators.