Description Some of the most important roles in American life have been filled by people born outside the United States. Immigrants have served in the military since the Civil War. Some immigrants have made fortunes and given them away - to create libraries, fund after-school programs, and protect citizens? civil rights. Still others have held political office or served our nation as ambassadors or - literally - rocket scientists. Here are 25 immigrants who have served our nation in these and other important ways.