Are the tactics planned out beforehand? Were messengers used to relay orders during battle? How efficient were their methods of relaying commands, if there were any methods of doing so at all? What about battles in which armies of the same side were separated by physical barriers (e.g. rivers, enemy army, etc.)?
IIRC, messengers or sounds (trumpets, drums, etc.) were used to signal.
However, they're not always effective. Ok. At the battle of Mantinea (418 BC) some ordering shenanigans occurred, with the following result.
We should note, as we start, that hoplite lines tend to drift towards their right. This happened at Mantinea, and the Spartan King Agis attempted to 'extend his left wing and to reinforce the attenuated line of battle with troops from the right' so, he wanted to move some troops from his right wing to the left. And thereby avoid being encircled. But, orders got confused, and two officers did not obey.
Oh dear. In the confusion, the Spartan line developed a giant hole in it, through which the enemy poured. But, the troops on the right rolled around, smashed the troops opposed to them, and then attacked the enemy centre.
So, very, very long story short: general screws up, hoplites win battle anyway.
hi! more examples are welcome; meanwhile, you may be interested in previous discussions on similar questions in the FAQ*
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