=4. The Northmen in Gaul.=--While this was going on in Britain, something of much the same kind was going on in Gaul. Throughout the ninth century the Northmen were plundering in Gaul, sailing up the rivers, burning towns and monasteries, and sometimes making small settlements here and there. But in the beginning of the tenth century they made a much greater and more lasting settlement. A colony of Northmen settled in that part of Gaul which from them took the name of Normandy, and there founded a new European state. This was in the year 912. The great dominion of the Franks under Charles the Great was now quite broken up into four kingdoms. That of the West-Franks, called _Karolingia_, because several of its kings bore the name of Charles, took in the greater part of Gaul. The crown was more than once disputed between the kings of the house of Charles the Great, who reigned at Laon, and the Dukes of the French, whose capital was Paris, and whose duchy of _France_ was the greatest state of Gaul north of the Loire. Some of these dukes themselves wore the crown, and, when they did not, they were much more powerful than the kings at Laon. But whether the king reigned at Paris or Laon, the princes south of the Loire, though they called themselves his men, took very little heed to him. Now when the kingdom was at Laon, the king was pretty well out of the way of invaders who came by sea; but no part of Gaul was more exposed than the duchy of France, with its long seaboard on the Channel, and with the mouth of the river Seine making a highway for the Northmen up to Rouen and Paris. Paris was several times besieged in the ninth century; and now at the beginning of the tenth, the coasts of Gaul, especially the northern coast, were ravaged by a great pirate-leader named Rolf--called in Latin _Rollo_ and in French _Rou_--who had got possession of Rouen and seemed disposed to settle in the land.