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Paludamentum, a military cloak, like that which the Greeks called chlamys. It was fastened with a fibula or clasp upon the right shoulder, in such a manner as to leave that side uncovered in order to give freedom to the right arm. This peculiarity gave rise to the occasional application of the term Paludati to warriors in general, although it properly belongs only to the chiefs who won the paludamentum. This mantle, not so large as the pallium, was easily put on and off, and adapted itself conveniently to service in the field.
When a Roman Emperor or General was on the point of setting out to take the command of his army, he went first to the capital, and was there invested with the paludamentum. On his return from the expedition, he threw off his war-cloak at the gates, and entered Rome clothed in the toga. This custom, it appears was so well established, that (according to Suetonius) Vitellius was looked upon as having committed, not only a novel but a tyrannical act, because he entered the city paludatus.
Septimius Severus, on the other hand, had the policy always to doff his soldier-like habiliments, and to assume the civil garb on such occasions. On the coins of this Emperor and his son Caracalla we see him with the fibulated paludamentum. Indeed, we are told by Spartianus, that he wore such scanty clothing that he scarcely had any purple vestment over his tunic, but covered his shoulders with a shaggy chlamys.
The cuirass and paludamentum often appear together. Some coins, however, present the figures of Emperors in the cuirass without the military cloak; yet the paludamentum over the tucked-up tunic is more rarely to be seen without the cuirass.