The Celts in Retreat
DURING the third century the Celtic world reached its greatest extent. In northern central Spain the Celtiberians had developed as a strong military force whose influence extended westwards to the Atlantic. To the north the Celtic language had long been spoken as far west as the Atlantic shores of Ireland, and elements of La Tène culture were well established among many of the Insular communities. South and east the Celts who had settled in the Po Valley and in central Asia Minor were harrying the Graeco-Roman world and earning their reputation as ferocious fighters. Smaller communities had spread around the northern shores of the Black Sea and others had penetrated northwards through the Carpathians into southern Poland. Isolated war bands had reached Delphi, mercenaries were operating in Egypt, and ambassadors had followed Alexander to Babylon.
The Second Punic War completely altered the balance of power in the Mediterranean. Rome moved into an expansive mode. From the end of the war in 202 BC until the capitulation of Numantia in 133 the Celtiberians and Lusitani were gradually brought under control. The first two decades of the second century saw the Roman armies win a series of major campaigns north of the Apennines paving the way for romanization, largely completed within a century. In Asia Minor the Celts of Galatia were brought to heel by the Roman army in 189 BC, after which, though still nominally free, their powers were progressively circumscribed.
In 133, the fall of Numantia in the west and the 'gift' of the Pergamene kingdom to Rome in the east, following the death of Attalus III, established Rome as a world power. Within a decade southern Gaul had been annexed, marking the first step in the systematic encirclement of the Mediterranean. At about the same time campaigns in the eastern Alps had extended Roman influence deep into central Europe. Along this immensely long interface, from the Pyrenees to the mountains of Illyria, the Roman world confronted Celtic tribes.