DD1's reading book tonight was an ORT Magic Key adventure, featuring soldiers hunting for someone's father. This is Oxford Reading Tree level 7, so aimed at infant pupils. Nothing gory, but set in the middle of the civil war. It was quite explicit about the fact that if the soldiers found daddy they would kill him.
DD1 is completely mystified about why everyone was so scared and what the soldiers were up to. It's lovely that she is so innocent, TBH. I found myself at a bit of a loss when she asked me what was happening. Does a 5 year old need to start knowing about these things? How could I have helped her understand the story without completely robbing her of the belief that people are nice and don't want to hurt each other? .
(We don't have a TV, so she isn't exposed to the news etc, which probably makes her more naive than most, but still.)