Alan Furst's mystery novels are must-reads for anyone who is interested in World War II.
A few of his minor characters reappear in subsequent novels (like the owner of the Brasserie Heininger in Paris), but the main character is not a lovable or crabby detective: it's the war itself. He moves around Europe in the series, from the Balkans to Belgium. His main characters tend to be somewhat ordinary people who didn't expect to find themselves in these situations. By focusing a microscope on one person's involvement--whether as a refugee or a businessman or a member of the resistance--he illuminates the entire era.
My favorite is "The Foreign Correspondent." But he's written a dozen or more, so you aren't going to run out of reading material quickly. The series does not have to be read in any particular order. Each book contains a map of the locations covered.
If you know a lot about this era, you'll enjoy Furst's dramatization of events (he does meticulous research). If you don't know a lot about WWII but non-fiction puts you to sleep, this is a painless way to understand the dynamics and dramas that unfolded in Europe during that time.