How can I find games based on Caesar's campaigns in Gaul and Britannia?
One great way to find similarly themed games is to consult the GeekLists on BoardGameGeek.


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For Caesar's Gallic War, I found this GeekList, Bellum Gallicum (58-51 BC) - Caesar Against the Gauls which appears to be a well curated list of 20 games dealing with Caesar and the Gauls.