[The Celts] lived in unwalled villages without any permanent buildings. They slept on beds of straw or leaves and fed on meat and were exclusively occupied with war and agriculture. . . . Each man’s property consisted of gold and cattle, as these were the only things that they could easily carry with them as they moved from place to place, changing their dwellings as their fancy determined.
They made a great point of friendship, for the man who had the largest number of clients or companions was looked upon as the most formidable and powerful member of the tribe.
Polybius, Histories (c. 150 bc)
Most of what we know about the customs and beliefs of the ancient Celts we owe to Classical Greek and Roman writers. These writers present a very consistent stereotyped picture of the Celts as a superstitious and savage people; economically backward, warlike and quarrelsome, emotional, boastful and vain, and fond of drink, feasting and song. This stereotype was not intended to flatter the Celts. Classical writers did find things to admire about the Celts, especially their courage, but, almost without exception, they regarded them as culturally inferior barbarians, who posed a deadly threat to the well-ordered, rational, urbanised Mediterranean world. Remarkably, the Classical stereotype lives on, though, thanks to the influence of the Romantic movement, it is now seen to be a rather positive one. The Celt has become the noble savage, uncorrupted and unrestrained by decadent civilisation. Under the impact of modern environmentalism and New Age beliefs, the Celts have come to represent all those virtues in which our materialistic society is most lacking, in particular spirituality and respect for nature. At their most idealised, for example, as presented at the Celtica visitor centre at Machynlleth in Wales, the Celts have come to resemble refugees from Middle Earth more than real people. There is also the other side of the coin. Because Western civilisation owes so much to the ancient Greeks and Romans, we tend to think of them as being much more modern in their outlook than they really were. In reality, the ancient Celts
Were much more like their contemporaries, the Romans, Greeks and also the Germans, than is generally recognised.