Curoas (Koo-roo-as) means "Paid Soldiers". These northerners are an excellent heavy infantry, well able to deal with most opponents.
The La Tene Celts were used as mercenaries all over Europe and Africa by the Romans, Carthaginians, other Celts, and various peoples. These men often form the core of a mercenary army, and are usually tough veterans who have seen many different campaigns and have taken pay from many different masters. They are an excellent heavy infantry, well able to deal with most opponents. They are armed with javelins and spears and use these javelins to break up an enemy formation before the charge. As with most Celts, the charge can become disorderly, but it often succeeds in breaking through the enemy line none-the-less. Their name, Curoas (Koo-roo-as) means "Paid Soldiers".
Historically, Celtic mercenaries were used all over the ancient world. Graves and artifacts have been found even into Asia. Celts were rightly famed for their ferocity in battle, as well as a number of innovations in arms and armor development. There were many Celts willing to leave their tribes and serve other masters in exchange for wealth. This made them somewhat untrustworthy, willing to flee if a battle went poorly, as they didn't fight for honor or glory, but money, and money was useless if one was dead. The La Tene Celts actually encompassed a number of sub-cultures, most notably Gaul, but also the Lugians, Belgae, most Britons, and others. This meant that in much of Europe, Celtic warriors were never far away, and so, for the wealthy general, he could have always had at least some heavy infantry on hand.
As they are the mercenary version of the Bataroas, their usage is basically the same, although they are not available in as large numbers as regulars and for a much higher price. Nevertheless, they will provide a useful additional force, which can be hired by everyone all over western Europe. They have acceptable offensive and defensive skill, as well as a quite acceptable morale. They are reliable troops which can be used as troops of the line, but the player must always keep in mind that they are unarmored and will suffer high casualties in prolonged melee or when exposed to missile fire.
Golberi Curoas do not have a high morale and can, especially when inexperienced and near a routing unit, begin to rout. However, the high lethality of their longswords, their javelins and also their high stamina make them determined flanking troops, especially useful against the unarmoured tribal warriors of northern Europe.
With a little micro-management, they are also very useful for factions campaigning in Iberia, especially for the Romani, who are a bit lacking in the high lethality department. They will be out-gunned by most Iberian units, but their swords will prevail in melee, where most Iberian troops have low-lethality, anti-armour weapons that are of little use against barbarian swordsmen.