The tribespeople who lived in western Europe before the Roman conquest were called Celts. Each tribe was made up of three main classes—druids, warriors, and farmers—and the largest settlements were hilltop forts.
Celtic warriors were famous for their love of feasting, fighting, and jewelry. They daubed their faces with a blue war paint made from woad (plant that produces a blue dye) and yelled at the tops of their voices as they rode into battle. But the terrible look and sound of a Celtic army was no match for the discipline of highly trained Roman legions.
After studying everything from herbalism to astronomy for up to 20 years, druids served Celtic society as priests and judges. At sacred pools, or groves of oak trees, they led religious rites that sometimes involved human sacrifice. Unlike most Celts, many druids could read and write.