Lorica segmentata

The lorica segmentata (segmented cuirass) is a type of personal armour used by soldiers of the Roman Empire, consisting of metal strips ("girth hoops" fashioned into circular bands), fastened to internal leather straps. The Latin name was first used in the 16th century; the ancient form is unknown.

The plates of lorica segmentata armour were soft iron inside and (some at least) were mild steel on the outside, making the plates hardened against damage without becoming brittle. This was a deliberate act, called case hardening, and is carried out by enriching the surface iron with carbon from organic materials packed tightly around the piece which is then heated in a forge. The strips were arranged horizontally on the body, overlapping downwards, and they surrounded the torso in two halves, being fastened at the front and back. The upper body and shoulders were protected by additional strips ("shoulder guards") and breast- and backplates. The form of the armour allowed it to be stored very compactly, since it was possible to separate it into four sections each of which would collapse on itself into a compact mass. The fitments that closed the various plate sections together (buckles, lobate hinges, hinged straps, tie-hooks, tie-rings, etc.) were made of brass. In later variants dating from around 75–80 A.D., the fastenings of the armour were simplified. Bronze hinges were removed in favour of simple rivets, belt fastenings utilised small hooks, and the lowest two girdle plates were replaced by one broad plate.

During the time of their use, this style of armour evolved and changed, the currently recognised types being the Kalkriese, Corbridge and Newstead types, named after their places of discovery. There was, however, a considerable overlap between these types in use and the Corbridge and Newstead types are often found at the same site (e.g. at Caerleon in Wales, Carnuntum in Austria, Carlisle in England and León in Spain). It is possible that there was a fourth type, covering the body with segmented armour joined to scale shoulder defences. However, this is only known from one badly damaged statue originating at Alba Iulia in Romania. The currently accepted range for the use of the armour is from about 9 B.C. (Dangstetten) to the late 3rd century A.D. (León). Its use was geographically widespread, but mail may have been more common at all times.

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