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.