Comments by "" (@neutronalchemist3241) on "Why Didn't Anyone Copy the Roman Army? - The Imitation Legions DOCUMENTARY" video.

Romans faced perfect "not Roman" legions during the social war. Those were the allies that traditionally provided half of the "Roman" army in the previous wars, so they used the same equipment, formations, logistics, command structure and tactics. Not by chance, famous Roman generals that won in the east with ridicolus ease, struggled in the social war, and it had been the only time when, shortly after having narrowly won, Rome granted to the former enemies all of their requests.
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@yulusleonard985 Romans infact faced perfect "not Roman" legions during the social war. Those were the allies that traditionally provided half of the "Roman" army in the previous wars, so they used the same equipment, formations, logistics, command structure and tactics. Not by chance, famous Roman generals that won in the east with ridicolus ease, struggled in the social war, and it had been the only time when, shortly after having narrowly won, Rome granted to the former enemies all of their requests.
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In the migration era, those were mass migrations of entire populations. Federations of tribes that gathered togheter exactly because the Romans could field tens of thousands of professional soldiers, so you needed hundreds of thousands of tribal warriors to beat them. For the pre-migration era armies, the difference is logistic. The ancient world was much more interconnected than the medieval one. That means that you could feed those tens of thousands of men by mining gold in iberia and using it to buy grain in Egypt. In middle age, apart for few merchants, trade was limited to the immediate neighborood.
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