Wikipedia and Google will both be excellent starting points as you research your topic.
Wikipedia is useful for its concise, easy to read overview of historical events and locations. More importantly, Wikipedia articles will link you to websites for museums, memorials, and social organizations. And, good Wikipedia articles cite academic sources like books and articles that you can find at K-State Libraries. Start with Wikipedia, but don't end here.
Google searches are another good way to explore existing information. Play around with your search terms and see what kind of websites and sources you discover. You may find an archive, a news/newspaper website, or other valuable resource.
When researching historical events that occurred in non-English speaking countries, be aware that the search terms you enter will produce different results. You are more likely to get English-language pages if you search in English -- e.g. Spanish Civil War -- than in Spanish -- e.g. La Guerra Civil.
Even if you do not speak Spanish or French, try using Spanish or French search terms to see the different search results you will find. You may discover a website, and archive, or a map that you would not have found otherwise.