Roman helmets: Imperial Gallic/Italic and Ridge - comparisons and sources

[Nathan Ross]

"above any impact force a human could produce reasonably"  They would prove to be an effective protection.

Yes, absolutely. Ridge helmets were clearly very effective protection. Their use at every level of the Roman army, from limitanei troops to emperors, virtually unchanged for c.160 years proves that.

"...helmet-bowls were designed out of two or more different pieces of iron, allowing for increased rigidity and a simplified manufacturing process"(Source below, pg 57). Note, not for increased strength.

Surely 'increased rigidity' would create 'increased strength'? What would be the purpose of rigidity otherwise?

the luxury of cost was seldom on the minds of those arming troops.

That would certainly be the case when the state was poor or needed to cut costs. But the Roman state was richer in the 4th century than it had ever been before, and did not run short of funds until the mid 5th century.

It's surely no coincidence that the introduction of the ridge helmet seems to have come at the time the imperial fabricae were set up. The Roman state needed a helmet model that could be produced in large numbers and to a high standard by a semi-skilled workforce on a production-line (we assume!). It was a need for increased efficiency that led to the change, not cost-cutting.

Incidentally, the Fernpass (or Bieberwier) helmet was made around the same time, with a single bowl. That - together with the much later Sutton Hoo helmet - demonstrates that Romans of this era were quite capable of forging single-bowl helmets if they wanted to. But the additional ridge on both the Fernpass and Sutton Hoo helmets may also suggest that a single bowl was not considered sufficient protection at this point.