I emphasised in my opening chapter the need, when studying Batavian ethnogenesis, to distinguish between the formation of the Batavians as a socio-political entity and their genesis as an ethnic group. This latter topic will be discussed in chapters 10 and 11. Central to the present chapter is the formation of the Batavians as a political community. I rely for the most part on historical sources. My investigation centres on the period from the mid-1st century BC until the Augustan era. This will involve some anticipation of the discussion of the political organisation of the later, pre-Flavian civitas Batavorum, which is the subject of chapter 8.

A reasonable argument can be made on archaeological grounds for regarding the Batavians in the Lower Rhine area as a newly formed tribe. Although Tacitus does refer to them as a splinter group of the Germanic Chatti who settled in an uninhabited part of the Rhine delta, the archaeological evidence suggests that they developed from complex, multi-ethnic origins. They were not simply a group of newcomers, but – in view of the considerable local continuity of settlement and material culture – included the remnants of older indigenous (probably Eburonean) groups as well. There emerged a new tribal association, a process which must have occurred in the course of a single generation.

The following discussion will cover three topics: the earliest history of the Romano-Batavian alliance, the probable role of a client kingship in this formative phase, and the introduction of an aristocratic order with a magistrature.

THE ROOTS OF THE ALLIANCE BETWEEN THE ROMANS AND BATAVIANS

According to Tacitus, the Batavians had a special alliance (antiqua societas) with the Romans in pre-Flavian times. The treaty regulated the supply of auxiliary troops in closed ethnic units and under their own commanders, and exempted the Batavians from paying tribute. Although the exact date of the treaty and the historical context in which it was made are unknown, it is generally assumed to have already been in place in 12 BC when Drusus used the Batavian region as a base for his campaigns into Germania magna. Willems has argued that the settlement of the Chatto-Batavian immigrant group in the Rhine delta somewhere between 50 and 12 BC was not a spontaneous process but was linked to Roman frontier policy.