High Imperial Roman army vs Late Roman army

[M. Demetrius]

A gladius is also a very effective weapon for drawing cuts (line on knee tendons) and slashing (like exposed limbs and necks). The belly thrust would most often cut into intestines, leading to fatal peritonitis, but that death is not immediate--regardless of what they show us on television. Exsanguination, on the other hand, if a thrust cut one of the large abdominal/thoracic arteries, would be just a matter of a half minute or so before the stabbed one lost consciousness due to shock and reduced blood pressure.

Late Roman spathae were not really intended to be used in the same way as a gladius, however, so it's not an easy comparison. The spatha more closely resembled a Gaulish sword, but it's clear enough that the Gauls were defeated by Republic armies, then Imperial armies. Spears were the main weapon of both late Romans and Gauls/Germanics/"Celts".

All these armies, from Republic to "barbarian" to Late Roman utilized light infantry whose primary initial weapon would have been javelins, slingers and archers. (Sorry, no TRW head hurlers) Late Romans had all these things plus the plumbata, a notably dangerous weapon.