By the 5th century BC vigorous Celtic tribes spread outward from their homeland east of the Rhine. They were equipped with iron weapons, so they were able to press forward into Gaul and Spain. Sometime later they crossed the channel into England.

The Celts, just as other Gaulish tribes, were drinkers and story tellers, and took pride in fighting. Their values contradicted their civilized Roman neighbors, so they didn't really get along well. The Celts pushed south through the Alps, raiding and pillaging along the way. They sucessfully sacked Rome in 390 B.C. Some Gauls stayed in Italy, while some moved in the Alps to the south of Milan.

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