I studied World History in college, and took only one U.S. History class on American Imperialism, focusing on the Spanish American wars. Prior to college, we had one U.S. History classes in 11th grades. I only remember early American history (e.g., Mayflower, Revolutionary War). Where did you live, that you were exposed to this information? and in what grade(s)? I should note that my public school education (such as it was) starting with 6th grade included a course in NC history. Slavery was not included as a topic. Yes, really. This was in 1965.