I am towards the end of ‘Dan Carlin’s Hardcore History - Celtic Holocaust’ podcast. I was just thinking about his discussion at the start. He kept using the quote, “ Celtic is anyone who identifies as Celtic.” . I would like to dive a tad bit deeper and maybe see if anyone here had a reasonable explanation. Would it be culture? Or would it be more so ancestor region? During the podcast, Dan usually just refers back to that quote to do away with the tedious topic of determination. I would love to hear from everyone. Thank you!
More could be said about this, especially when it comes to the history of modern Celtic identities in Ireland, Scotland, Brittany, etc. but you might be interested about this previous answer about the different meaning of Celts in antiquity.
What were the biggest differences between the Gauls and the Celts?.
This is not your question, but I'd strongly advise you not to take Dan Carlin's podcast episode as representative of what's known or hypothesized about late independent Gaul and the Gallic Wars : the whole label of holocaust and genocide is historically very flawed and frankly morally wrong, which can be attributed to the extreme paucity of sources used in the making (three, including two different translations of Caesar's commentaries).