What then was the real source of Neolithic progress?[173] It is not to be sought in great wars and revolutions. Genuine wars are carried on by nations with a national government, and as yet there were no nations, and even tribal government--outside of religion, the great bond of tribal unity at this stage--was probably weak, loose, and inefficient. There were no such strong towns or city-states as sprang up later in Greece. There were here no nomadic hordes to be driven by drought from their withering pastures to migrate _en masse_ and force their way into less thirsty and starving regions. There was, as yet, no great overpopulation of mountainous areas compelling raids or forays into piedmont zones. The nearest approach to this condition is the slow, evidently peaceful penetration of parts of France by broad-heads from its eastern uplands filtering in and mixing with the long-headed older population, and betraying their arrival mainly by a change in form of head and rise of cephalic index. There was little wealth to tempt invasion. There were no cities or large towns to plunder. There were wide stretches of land thinly or not at all populated and open to any newcomer. All that we know of Neolithic religion, far more dominant in tribal life and action than the very feebly developed political or social organization, the cult of the goddess, and the accompanying mother-right, suggest peace. The great invasions of the Bronze and Iron periods introduced or stimulated the cult of war gods and patriarchal family life and kinship. But these were still in the future. The picture of Europe at this time as a great arena of roving savages, thirsting for blood and always at war, seems to be a caricature. The people of the banded pottery were evidently peaceful. They left no weapons except mattocks and hammers. No one, I believe, has ever accused the broad-heads of blood-thirst. The graves of northern hunters with corded pottery are all about Grosgartach. The little village was deserted and decayed. It showed no signs of having been burned. The lake-dwellings were open to attack at all times, especially after the ice had formed during the winter. Robenhausen during its long history burned several times; hardly as often as most of our New England villages. Here a single brand or fire-tipped arrow in a thatched roof would have destroyed the whole settlement. Only in northern Europe, in the country of the corded pottery, do we find great attention paid to the making of fine weapons like the flint daggers and axes. Here we have chiefly herdsmen and hunters. Here there were probably village incompatibilities--Donnybrook fairs, cattle-lifting, and forays. But these should hardly be dignified with the name of wars. We find then some North German peoples at the very end of the Neolithic period pushing southward, often by peaceable infiltration, sometimes perhaps by violent incursions, when the resistance was great.[174]