I tried a "one change only" rule on a Rome never fell timeline and it broke my whole map
Last month I tried running an alt history where Rome never fell but I only changed one thing, the Battle of Actium in 31 BC, and let everything else play out. By the year 1500 my map had a Latin-speaking superstate, a Norse empire in the Baltics, and no Age of Exploration, and it took me 3 notebooks to trace why the changes kept snowballing. So how do you all keep a single change from rewriting the entire world map?