See Boudica's speech

Appian's Account

Nor was Suetonius silent at such a crisis. Though he confided in the valour of his men, he yet mingled encouragements and entreaties to disdain the clamours and empty threats of the barbarians.

"There, you see more women than warriors. Unwarlike, unarmed, they will give way the moment they have recognised that sword and that courage of their conquerors, which have so often routed them. Even among many legions, it is a few who really decide the battle, and it will enhance their glory that a small force should earn the renown of an entire army. Only close up the ranks, and having discharged your javelins, then with shields and swords continue the work of bloodshed and destruction, without a thought of plunder. When once the victory has been won, everything will be in your power."

Such was the enthusiasm which followed the general's address, and so promptly did the veteran soldiery, with their long experience of battles, prepare for the hurling of the javelins, that it was with confidence in the result that Suetonius gave the signal of battle. [Tac. Ann. 14.36]

Caesar

Having encouraged the soliders with no further speech than that

"they should keep up the remembrance of their wonted valor, and not be confused in mind but valiantly sustain the assault on the enemy",

as the latter were not further from them than the distance to which a dart coul dbe cast, he gave the signal for commencing battle.