How well armoured was the Roman army?

[Matthew Amt]

Is it correct that the legionairs quit using the humeralis of the Lorica Hamata sometime during the 1st century AD? If so, can someone tell me a specific time frame (mid or late first century)?

Ave! Sorry, not sure I understand the question--what is "humeralis"? Legionaries did not stop wearing lorica hamata (mail armor) when the lorica segmentata appeared. Some wore one type, others wore the other, and some were not armored. If you just mean the flaps or shoulder doubling/reinforcing on the hamata, that is still seen on the Adamklissi monument dating to Trajan's Dacian campaigns. However, Trajan's Column also shows mailshirts without shoulder flaps, so there were different styles at use for a while.

It is interesting to consider why the Romans gave up protection against arrows. Perhaps they thought that is what the shield is for?

They didn't. Mail works just fine against arrows, or it would not have been used by so many Roman troops, including officers and standard bearers. In fact, since the lorica hamata of the 3rd century is a little longer than a segmentata and has sleeves, it gives *more* protection than a segmentata. Though it is certainly true that the shield was always the first line of defence! Remember that there were always some legionaries who had no body armor, and that does not seem to have been seen as any terrible problem or disadvantage.

I read somewhere that segmentata was designed after rome's longterm encounters with parthian archers:

Well, that seems to be about right as far as the timing goes. But we can not say that those encounters are *WHY* the segmentata developed, unless there is a clear reference in ancient literature to that effect. The reasons for Crassus' defeat are complicated and much debated, but it certainly wasn't as simple as "mail is no good against arrows". The Romans did beat the Parthians sometimes, after all!

Matthew