Late Roman Unit Sizes

[Renatus]

Adrian wrote:
Its clear in one instance that it meant troops taking off their armour and just relying on their shields to defend themselves.

Why would they take off their armour to defend themselves? Isn’t the point of armour to is to protect?

Adrian is probably thinking of Zosimus 4.25.2-3, in which a Roman force under a commander named Modares launched a night attack on a band of drunken Goths, catching them unawares and slaughtering them. In Zosimus' words, " . . . he quietly ordered his men, armed only with swords and shields and disdaining heavier armour, to abandon the usual fighting in close order and attack the barbarians while they were paralysed by their indulgences" (Ridley's translation). No doubt, they dispensed with armour in the interests of speed and silence.