The Italic peninsula in the 5th and 4th centuries BC is a confusing patchwork of many ethnic and political entities. The early Roman Republic was as yet a small and unassuming community in the midst of several other Italic peoples, the Etruscans, the Greeks, and the Carthaginians. Apparently it was with Carthage that the young republic concluded its first treaties. Later, Rome and Carthage would get involved in a struggle for life and death, but at this stage Rome was preoccupied with other opponents. It got drawn into conflict with several Italic peoples, among whom were also their direct neighbors, the Latins; with the Etruscans; and from around 400 BC with the Celts, who had invaded the Italic peninsula and were pushing south. The Celts were an especially dangerous enemy: early in the 4th century BC, on one of their raids, they even managed to occupy Rome. This and other setbacks were, however, temporary, and did not stop Rome from conquering in the 4th century BC, in rapid succession, large parts of Italy.
To the west and north of the Alps, the Celts were the most important presence. What actually should be understood by the designation “Celt” is not very clear. Only the period of the so-called Latene culture (about 480-15 BC), a cultural complex stretching from France to Bohemia, can be said to be Celtic with certainty. Now, the Latene culture is not completely different from the preceding Hallstatt culture (from about 750 BC), and one may judge this to be a case of cultural continuity. Discontinuities, however, are evident as well. Thus, we cannot call Hallstatt Celtic just like that. We are speaking of the Hallstatt cultural complex that is only known from archaeological finds, and which is difficult to pin down regarding ethnicity or language.
Already in the Hallstatt period, social differentiation is quite marked, as can be seen from the rich burials that have been discovered. From the 6th to the end of the 4th century BC, men, women, and even children (which indicates hereditary status) of the social layer that dominated society militarily, politically, economically, and possibly also religiously, were buried with costly grave goods, including items imported from the Mediterranean. The main status symbols of this aristocracy were four-wheeled carts and two-wheeled chariots, the chariots being especially in evidence during the Latene period. Local power was established in hilltop strongholds, so-called Herrensitze or Furstensitze, where trade and crafts were also concentrated. There is unmistakably much Greek-Etruscan and Greek influence, arriving from across the Alps and along the valley of the Rh<3ne, respectively. The Gefolgschaft, a group of warriors bound by ties of patronage to an aristocrat, can safely be expected to occur already in the early period, even if it is documented only for a much later date. Celtic society had non-farming members, craftsmen and warriors, and both groups were employed by patrons. The presence of Celtic mercenaries in the Mediterranean world from 400 BC onward fits this picture. And also the expansion of the Latene-Celts toward the south and east during the 4th and 3rd centuries BC has been linked to the phenomenon of the Gefolgschaft.
Even when Celtic power was at its height, not all of Western and Central Europe was Celtic. On the Iberian peninsula, we had Iberians and Basques; in the south of France and on Corsica, there lived Ligurians; in the Alps were many different tribes; and from Central Germany up into southern Scandinavia could be found Germanic tribes.