Quote Originally Posted by Theodotos I
Was it common practice for a man’s shield to be carried into battle by another man, or was this practice restricted to war-leaders and champions? In such a case, where would the “shield-bearer” go during the battle?
I can think of two cases of this sort of thing happening during or near our time period. In both cases, three men are apparently bearing shields solely to protect the commander during combat.

In the first case, Diodorus Siculus (20.52) is describing the naval battle of Salamis (off Cyprus, not Attica) in 306 BC:

Demetrius fought most brilliantly of all, having having taken his stand on the stern of his seven [heptere]. A crowd of men rushed upon him, but hurling his javelins at some of them and by striking others at close range with his spear, he slew them; and although many missiles of all sorts were aimed at him, he avoided some that he saw in time and received others upon his defensive armour. Of the three men who protected him with shields, one fell struck by a lance and the other two were severely wounded.
The second case occurs as Polybius (10.13) tells of Scipio's assault on Nova Carthago in 209 BC:

All this time Scipio himself had by no means remained aloof from the fighting, but had also taken all possible precautions for his safety. He had with him three men carrying large shields, which they held so as to cover him completely on the side which was exposed to the wall, and thus protected him from missiles.