Legionaries with small, round shields

[Justin of the New Yorkii]

So I was watching a good documentary about Rome the other day, and in a piece about the Crisis of the Third Century they briefly showed two sepia-tone legionaries fighting in slow-motion while the narrator spoke.

They were more or less accurately depicted, but they had small, round shields. I'm not talking about the bigger oval shields like those used at the Battle of Milvian Bridge; these were almost as small as a buckler, like something a gladiator would fight with.
It wasn't footage of a battle, just a clip of two guys dueling to sort of represent the Crisis of the Third Century visually while the narrator spoke.

Was this just done for the aesthetic of the camera shot, because the bigger, more accurate shields would block the view of the men?
Or were there actually Roman legionaries were equipped with smaller shields for specific tactical applications?

I would assume the former, but if you think about it the smaller shield would have its advantages too in certain situations.

[The Alexandrian]

In the Republican era, at least as late as Marius' war with Jugurtha, the fittest young legionaries were used for special light duties as 'extraordinarii' or 'antesignani', and I have seen them reconstructed as being unarmored and fighting with bucklers; Sallust describes light legionaries using small Numidian-style hide shields. So there is evidence for legionaries - not just auxiliaries as commonly thought - fighting unarmored and/or with lighter equipment such as round shields.

Much closer to the time period in question we have the lanciarii - who have been interpreted both as light legionaries with smaller shields and more javelins, or as normal legionaries fighting with a different type of javelin (lancaea) than the traditional pilum. At least at Nisibis (217 AD), the lanciarii seem to have functioned more like the light antesignani and velites of Republican days - who fought with round shields. It is entirely possible, especially in the chaotic period of 235 - 284 AD, that there were legionaries, perhap specialist lanciarii, fighting with round shields. If I recall correctly, the last evidence for the traditional rectangular scutum comes from coins of Gallienus issued in the early 260's.

But I have a hard time seeing why traditionally armored legionaries with chainmail and helmets would use anything other than oval or rectangular body shields - I agree with you in saying that the makers of the documentary were probably being either sloppy or fanciful in giving their legionaries round shields.

[Justin of the New Yorkii]

Thanks Jon for the info. Small shields might be useful for mining and counter-mining, or for scaling walls with a ladder, but if the need came up I suppose you could always just grab a spare cavalryman's shield.

If memory serves correctly, the Philistines used to have their main body of troops armed with large, rectangular shields and spears, but they would complement them with sickle swordsmen who had small round shields because it's easier to attack quickly in all directions with a smaller shield.