Hi everybody !
I love your work guys. But there is a lot of big historical problems with your rendering of the Celts. I'm a french historian and archeologist, and i can say that you have used pictures and references which date from 50 years ago. There are many publications in french scientific research about the Celtic armament. I will try to summarize :
Third century BC : there were the linothorax and leather armor with colorful patterns and "vegetable style" (mainly known by the statues of Roquepertuse and Entremont (Salyan territory, in the south of France)). The "vegetable style" found also certainly on the shields. Helmets are mainly Montefortino type with some variations. Chainmail starts to spread. Spears have sharp, long and narrow peaks in the first rank (for sinking into shields and destabilize the enemy), and wide and short for men in the second rank (to avoid that the blades dig into shields : the warriors can continue to support the men of the first rank, at least that is what shows the experiments conducted by Matthew F.). The sword is short and sharp.
First century BC : chainmail is democratized (but still remains the prerogative of professionals, ambactoi or solduroii). Linothorax with colorful and vegetable style has disappeared, there is still leather armor, but we don't know the patterns (we went in a figurative and non-plant art at that time). The shields are sometimes develop with circular umbos. Montefortino helmets are very rare, but there are still very elongated versions, with a summit button). There are especially Port and "Western Celtic" types (cf. the "helmet of Alesia") that prevail at this time . A sword specially designed for riders emerged: long and rounded at the end (but pedestrians keep short and sharp model more efficient to hit thrusting).
The bronze armors disappeared at the end of the Hasltatt period (end of the Fifth century BC). It seems that never Celts use axes to fight. The shields are always oval (cf. the shields of the site lake of La Tène). And these famous "Gallic mustache" in no way represent the historical reality. One passage Strabo tells us that "some noble loved wearing the mustache." It is therefore far, far away a generalized port. Also recall that Caesar, which loves friant details and oddities for his readers, make no reference of that (a sign that the mustache was far from universally popular ...).
If yo want a good representation of the appearace of the Ancient Celts, look the very good "comics" : "le Casque d'Agris" (III century BC) et "Alesia" (First century BC), both write with the help of the french archeologists.
I hope it was helpful. And sorry for my bad english

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