They traveled with their men just to scream at them during the fighting.
At the 58 BC Battle of Vosges, Julius Caesar was surrounded. He had to force the Germanic army under Ariovistus into combat because the German was content to starve the Romans out. Cut off from supplies, Caesar's legions may not last long enough to attack later. So, outnumbered and surrounded, Caesar struck.
He marched his entire force toward the weakest part of the Germanic army: its camp. When the legions arrived, the Germanic women were in the army's wagon train, shouting, screaming, and wailing... at the Germanic men.
Julius Caesar meets Ariovistus before the Battle of Vosges.
The Gallic Wars were an important moment in the history of Rome. It saw Julius Caesar's rise in power and prestige as well as an important military and territorial expansion of the Roman Republic. But to the Romans' well-organized and disciplined fighting force, the wailing Germanic women must have been an altogether strange experience.
Germanic women were forced to defend the wagon trains after many battles against the Romans.
If a tribe was caught up in a fight while migrating or moving for any reason, women would not be left behind. Germanic women would yell at their fighting men, sometimes with their children on hand to witness the fighting. The women encouraged their children to yell and, with bare breasts, shouted reminders at the men that they must be victorious in combat or their families would be captured and enslaved... or worse, slaughtered wholesale.
Their shouts encouraged their men to fight harder, as women were considered holy spirits. Letting them fall into enemy hands was the ultimate failure.
The Roman Senator and historian Tacitus wrote in his work, Germania:
A specially powerful incitement to valor is that the squadrons and divisions are not made up at random by the mustering of chance-comers, but are each composed of men of one family or clan. Close by them, too, are their nearest and dearest, so that they can hear the shrieks of their women-folk and the wailing of their children. These are the witnesses whom each man reverences most highly, whose praise he most desires. It is to their mothers and wives that they go to have their wounds treated, and the women are not afraid to count and compare the gashes. They also carry supplies of food to the combatants and encourage them.
It stands on record that armies already wavering and on the point of collapse have been rallied by the women, pleading heroically with their men, thrusting forward their bared bosoms, and making them realize the imminent prospect of enslavement -- a fate which the Germans fear more desperately for their women than for themselves. Indeed, you can secure a surer hold on these nations if you compel them to include among a consignment of hostages some girls of noble family. More than this, they believe that there resides in women an element of holiness and a gift of prophecy; and so they do not scorn to ask their advice, or lightly disregard their replies.The women were more than just morale builders, though. They provided aid and comfort to their men after the battle was over, of course. And they would bring supplies and food to their male warriors in the middle of the fight.
If the battle didn't go well, however, Germanic women could take on an entirely new role. They might kill any male members of the tribe who attempted retreat. They could even kill their children and then commit suicide rather than submit to enslavement by another tribe or army.
Women were captured en masse at the Battle of Aquaq Sextiae.
Vosges wasn't the first time the Roman Republic encountered this phenomenon. At the 102 BC Battle of Aquae Sextiae a Roman army that was outnumbered by Germans 3-to-1 emerged victorious, according to the Roman historian Plutarch. He notes that 300 of the women captured that day killed themselves and their children rather than be taken back to Rome.
For the Germans at the Battle of Vosges, the situation wasn't as desperate. They were all well-rested and their march from the Rhine River didn't take a heavy toll on their strength. But the Romans were formidable and, thanks to a sudden moment of quick thinking by one of Caesar's cavalry officers, they were able to drive the Germans back across the Rhine. When Caesar returned from Rome after the conquest of Gaul, he came back with a million slaves.