Organised Celts - Unbeatable?

[CirdanDharix]

I think part of the whole "if the barbarians would be united, the Gods themselves would be needed to save us!" thing was the supposition that there were alot more of "them" than there were of "us". That's certainly the case for when Herodotos states that, if united, the Thracians would be invincible. In fact, all of the barbarians could be, and were, defeated in pitched battles with organised armies--the only exception here being horse archers from the steppes--but their strength lay in 'irregular' warfare; with a very large protion of their population under arms, but generally sparsely populated and 'wild' territory--think of the Germanic forests--they had an easy time mounting guerilla operations against invading armies, which would find it hard to supply themselves and be worn down by the constant attacks. It's also the case that often the barbarians would outnumber the 'civilised' folks, even with a less dense population: less slaves, no equivalent to metics/perioeci, and most of them expected all adult males to have at least some simple weapons (like a spear and shield) and to know the basics of using them; some barbarians even resorted to dastardly tactics like allowing women to fight! How uncivilised. Oh, and I forgot to mention, that barbarians generally had an abundance of light troops, that might not produce a great effect during massed battles, but could be very difficult to actually defeat.