The Celts is really a rather large term used to define any number of tribal societies in Europe that spoke variations of Celtic languages. They went on to spread into much of Central and Southern Europe as well as the British Isles and were in some ways the origin of tribes like the Gauls who played an integral role in the beginning of the destruction of the Roman Empire.
Descriptions of their society are mainly derived from large amounts of archeological evidence as well as some of the accounts of various Roman historians that documented what they knew about these tribes at the time of their encounters with them.
The Celts were a group of peoples that occupied lands stretching from the British Isles to Gallatia. The Celts had many dealings with other cultures that bordered the lands occupied by these peoples.
The first historical recorded encounter of a people displaying the cultural traits associated with the Celts comes from northern Italy around 400 BC, when a previously unkown group of barbarians came down from the Alps and displaced the Etruscans from the fertile Po valley, a displacment that helped to push the Etruscans from history's limelight.
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