When Did The Roman Army Standardize Using Plate Armor?

[Caratacus]

"Plate" amour (more commonly known as lorica segmentata) was first noted in the archaeological record at a site called Dangstetten, in Germany, some time between 15 and 9 BC. This was the so-called "Kalkriese" form of the armour, where the fitments/leather straps were riveted directly to the iron plates. The name reflects the site of the Varus defeat in 9AD, where some of the fitments were discovered, but the armour was in use some 20 years before that. Evidently, this design was unsatisfactory because it was replaced by the "Corbridge" form, where the leather straps were sandwiched between two layers of brass strip and the rivets were then passed through this sandwich into the iron plates. This form of the armour was in use for the majority of the 1st CAD and into the 2nd CAD. However, this was also unsatisfactory, because a further form came in to use that overlapped with the Corbridge form. This third form is known as the "Newstead" form. It had fewer plates than the Corbridge type, the shoulder hinges were much larger and the method of closure of the girdle plates differed. To that extent, the armour was not 'standardised' - it was, however, developed over a period of time when the perceived weaknesses of the armour were systematically addressed and corrected. Eventually, its use was discontinued because the tactical situation for the Romans changed. Heavy infantry 'shock troops' were just too slow to get to the site of an incursion by mounted enemies from the East. The last recorded find of the armour is from a temple at Stillfried, around 260 AD. This may have been a votive offering.

These different forms of the armour were in use for decades and in many cases the Corbridge and Newstead types are often found at the same sites. To the degree that we can say that the armour was 'standardised' it is worth noting that fragments of the armour (mostly the brass fitments) occur at multiple sites, many of them in the UK but also along the Rhine/Danube frontier. In all these cases the measurements of the pieces show a remarkably constant size. The plates themselves are also very constant in terms of thickness, which has led to the suggestion that the iron plates may have been rolled rather than beaten - or that hammers with larger heads were employed.

The Adamklissi monument does not show any figures wearing the plate armour. However, what it does show are many examples of Roman infantry fighting tactics, such as a thrust around the outer edge of the shield into the lower abdomen of the Dacian warrior. The whole style is that of the early 2nd CAD, certainly not medieval. The sculpture is actually quite crude, although accurate. It has been suggested that the sculpting was carried out by the soldiers of Trajan's army, which might account for the crudity of the figures. Some 46 of the figures (the metopes) are now housed in a purpose-built museum adjacent to the monument site (probably one of the most useful thing that the communist government did.)

A very detailed monograph on the armour was written by Dr Mike Bishop (JRMES, Lorica Segmentata Monograph No.1 and a second Monograph listing some 1,600 finds of the armour was my own contribution (JRMES Lorica Segmentata, a catalogue of finds, M.D. Thomas).