The borders of modern France closely align with those of the ancient territory of Gaul, inhabited by the Gauls, a Celtic people. Gaul was conquered by the Romans in the first century BC, and the Gauls eventually adopted Romance speech and culture. Gaul's eastern frontiers along the Rhine were overrun by Germanic tribes in the fourth century AD, principally the Franks, from which the ancient name of "Francie" derived. The modern name "France" derives from the name of the feudal domain of the Capetian Kings of Francia (France) around Paris. [source: http://en.wikipedia.org/wiki/France]

The name France comes from the Franks, the Germanic tribe that occupied the region after the fall of the Roman Empire, and, more precisely the region around Paris called lle-de-France which was the centre of the French royal dominion. The borders of modern France roughly align with those of the ancient territory of Gaul, inhabited by Celts known also as Gauls. Gaul was conquered by the Romans in the first century BC, and the Gauls eventually adopted Roman speech and culture. Christianity also took root in the second and third centuries AD. Gaul's eastern frontiers along the Rhine were overrun by Germanic tribes in the fourth century AD, principally the Franks, from whom the ancient name of "Francie" derived. The modern name "France" derives from the name of the feudal domain of the Capetian Kings of France around Paris. Existence as a separate entity begins with the division, in 843, of Charlemagne's Carolingian empire into eastern, central and western parts. The eastern part (which would soon unite with the central portion as the Holy Roman Empire) can roughly be regarded as the beginnings of what is now Germany, the western part, that of France. http://en.wikipedia.org/wiki/France

From the Franks (a Germanic tribe) when they over ran Gaul (modern day France)

The name France comes from Latin Francia, which literally means "land of the Franks, Frankland". Originally it applied to the whole Frankish Empire, extending from southern France to eastern Germany. At the Treaty of Verdun in 843, the Frankish Empire was divided in three parts, and eventually only two: Francia Occidentalis (i.e. "Western Frankland") and Francia Orientalis (i.e. "Eastern Frankland"). The rulers of Francia Orientalis, who soon claimed the imperial title and wanted to reunify the Frankish Empire, dropped the name Francia Orientalis and called their realm the Holy Roman Empire (see History of Germany). The kings of Francia Occidentalis successfully opposed this claim, and managed to preserve Francia Occidentalis as an independent kingdom, distinct from the Holy Roman Empire. The Battle of Bouvines in 1214 definitely marked the end of the efforts by the Holy Roman Empire to reunify the old Frankish Empire by conquering France.