Caesar. De Bello Gallico I.1. Gallia est omnis divisa in partes tres, quarum unam incolunt Belgae, aliam Aquitani, tertiam qui ipsorum lingua Celtae, nostra Galli appellantur.

NOTES (from Caesar. De Bello Gallico I. Ed. C. Ewan. London: Bristol Classical Press, 2000, p. 65.

          This chapter gives a short geographical and ethnographical sketch of Gaul. It is meant to focus the minds of readers on the essential facts of the Gallic and German situation. 

1. Gallia. In Caesar’s time, this might mean either Cisalpine Gaul – Northern Italy – or the Roman ‘province’ of Gallia Transalpina, also called Narbonensis, Ulterior, and Bracata (‘where-they-wear-breeches’); or, more generally, the whole area where the Gauls lived – modern France, with part of the Low Countries, Switzerland, and Northern Italy besides. Caesar here means the whole area.

1.     omnis. Not ‘all Gaul’ but ‘viewed as a whole.’