Hearts of Iron IV has an incredibly robust mod scene, probably one of the best among Paradox grand strategy game. HOI4 mods are one of the main reasons that it's also the most consistently popular out of all of the strategy games Paradox Development Studios produces, even compared to Crusader Kings III.
There are so many mods that you could play repeat games of Hearts of Iron IV and experience a range of different time periods, right through to the post-apocalypse wastes of the Fallout series. There is a rich, complex web of alt-history and historical fantasy mods, but there are so many choices it can be hard to figure out where to start.
Thankfully, user AnonymousFordring from the HOI4 subreddit has come to our rescue. They've put together a semi-humorous take on how you can navigate the myriad of key timeline mods that exist for the WW2 war game, starting with The Coming Storm. This is a mod in the early stages that covers the time period of the First World War, from 1905 to 1923. You could also try out The Great War, which is a more focused and popular WW1 mod.
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