The Celts come from Central Europe. The Celtic civilization as such developed from 1100 BC: the period of the Hallstatt (in yellow on the map below) is referred to.
After this phase of Organization of the Celtic Society, the so-called “De La Tène” period (between 450 BC and 25 BC) sees the migration of the Celtic peoples mainly towards western Europe (in light green on the map below). The Celts settled in Gaul but also in Belgium and the British Isles.
The arrival of the Celts in the territory of the megalithic peoples
Before the arrival of the Celts, the indigenous tribes, called “megalithic peoples,” were settled on the land which, later, Julius Caesar named “Gaul.” The megalith tribes live from gathering and hunting and are mostly nomadic.
The arrival of the Celts is carried out gradually, and the population mix between the Celts and the megalith peoples is carried out in a generally harmonious manner. Indeed, these two peoples have common customs and a similar way of life, although the Celts have developed a much more hierarchical and codified society.
Legacy of the Celtic and Romanization of the Gauls
Celtic culture is somewhat neglected by the Gallo-Roman society. It must be said that the lifestyle carried by the Romans offers many advantages. Indeed, the organization of society is well structured, and the quality of life is undeniable. The thermal baths are dedicated to hygiene and well-being, while the theatres provide entertainment for the population.
Namely: the megaliths were pagans who worshipped the elements (water, fire, or the sun, for example). The Celts, on the other hand, had Gods to whom they devoted much more organized worship.
The Celts are a protohistoric civilization of emigrant peoples throughout Europe and Asia. The Celts had a vibrant culture that flourished during the Iron Age and developed an abstract art whose value is now recognized. The Celtic culture has survived many years until the Middle Ages in Ireland, before the disappearance of the evangelization of the island by Saint Patrick in the 5th century. The Celts belong to the family of Indo-European peoples.
Not knowing any political unity, the Celts were a myriad of peoples with different laws, customs, and rites. They are best known in ancient Greek and Roman texts (in particular thanks to Caesar) for their warrior value, their carried-away character, their constant infighting and for the mysteries of Celtic mythology. The Celts did not constitute a bloody and destructive civilization as ancient authors have often written, although they are known to have practiced human sacrifices and to have devoted a cult to Severed Heads, notably at Diodorus of Sicily.
They could not probably unite and found larger political entities than the city or the Confederation of peoples that lost them: it seems that, like the archaic Greeks, the Celts hated centralism and knew only temporary alliances based on clientelism. The history of the Celts is marked by a succession of conquests and migrations (until the 2nd century BC) that led them to Asia Minor. After a series of military setbacks in the Gallic War from 58-51, all Celtic peoples surrendered to the Romans, except in the British Isles and Ireland.
We do not know the name or names by which the Celts called themselves as a people, if at all they did. The word “Celtic” has come to us through the external civilizations that have been with them. The primary testimony comes from Julius Caesar.