How did ancient peoples identify themselves?

[cmacq]

I was wondering how they would identify who was friend and who was foe on the battlefield

By their slogan, colours, and mark. Of course, a slogan is the war cry and in Scots Gaelic ours is, 'An t'Arm breac dearg.' In English, 'Our Weapons speckled red,' I think meaning 'speckle Our Weapons red?' Some bloody fool on the net claims it means, ‘the red-tartaned army.’ Not even close, as the only word they got right was 'red' for 'dearg.'



As you see the colours are red, and the mark, the way one looks, talks, walks, sets, and stands; as well as the weapons, and how they're made to sing by your hands.