I love ancient warfare. The history, tactics, the campaigns its so ancient, distant, its almost like fantasy. The battles such as Thermopylae, are noble, glorious, maybe even romantic.

Are there any sources that paint the darker side of ancient warfare? The detail of the heat of battle? The unimaginable violence.

What it was like to stand in the front line holding your shield tight and bracing for the impact of the charging Celtic enemy. To be at the front of the legion, your shield arm is almost numb, your so exhausted every thrust/ slash of your gladius is agony.

What it must have been like to thrust your spear into the face of your opposing enemy, step over him and allow the men in the ranks behind you to finish him of, making sure he doesn't get back up.

To have to hack through a mans desperately raised hands and forearms to deliver the killer head blow.

To stand in the baking sun after a grueling, grinding battle, you so exhausted your nearly sick, dehydrated, light headed, covered in blood only to raise your aching head to see fresh enemy troops formed up and heading to your position.

Is there any sources that identify the psychological impact that battle/war must have had on some soldiers?