Brythonic. Transalpine Gaul was probably invaded by Aryan-speaking Celts
from more than one direction, and the infiltration and invasion of new-
comers, when it had once begun, was doubtless continuous through these
various channels. There are cogent reasons for thinking that ultimately
the dominant type of Celtic speech over the greater part of Gaul came to
be that of the P rather than the QU type, owing to the influx from the
East and Northeast of an overflow from the Rhine valley of tribes
speaking that dialect; a dialect which, by force of conquest and culture,
tended to spread farther and farther West. Into Britain, too, as time
went on, the P type of Celtic was carried, and has survived in Welsh and
Cornish, the remnants of the tongue of ancient Britain. We know, too,
from the name Eporedia (Yvrea), that this dialect of Celtic must have
spread into Cisalpine Gaul. The latter district may have received its
first Celtic invaders direct from the Danube valley, as M. Alexandre
Bertrand held, but it would be rash to assume that all its invaders came
from that direction. In connection, however, with the history of Celtic
religion it is not the spread of the varying types of Celtic dialect that
is important, but the changes in the civilisation of Gaul and Britain,
which reacted on religious ideas or which introduced new factors into the
religious development of these lands.

The predatory expeditions and wars of conquest of military Celtic tribes
in search for new homes for their superfluous populations brought into
prominence the deities of war, as was the case also with the ancient
Romans, themselves an agricultural and at the same time a predatory race.
The prominence of war in Celtic tribal life at one stage has left us the
names of a large number of deities that were identified with Mars and
Bellona, though all the war-gods were not originally such. In the Roman
calendar there is abundant evidence that Mars was at one time an
agricultural god as well as a god of war. The same, as will be shown