Obviously the Second World War was horrible, but it makes for one hell of a setting for historical fiction. If at the heart if every good story is a conflict, then the middle of the 20th century is the place for story writers to look.
The obvious topic for Second World War fiction would be the frontlines, battles and survival. Saying that, there is a surprising number of very popular romance novels set during wars, and WW2 is no exception. There is also a lot of very moving fiction set in bits of occupied Europe, people living under brutal foreign rule against the background of armed conflict. Horrible, but compelling stuff.
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