By the year 1070 the conquest of England by William I was complete, and all the available sequestrated lands had been divided among his followers. But the land hunger of the barons was unappeased; and in order that he might have time to consolidate and to organize his new kingdom, William directed their attention to Wales. That country possessed three obvious gates by which invading armies might enter. The first was Chester, which William himself had visited, and from which the great mountains of Gwynedd could be clearly discerned. The second was Shrewsbury, from which a broad and fertile valley stretched right into the {67} heart of Powys. The third was Hereford, the natural starting point for the conquest of Deheubarth. At each of these points William stationed one of his barons--at Chester the rapacious Hugh the Wolf, at Shrewsbury the able Roger of Montgomery, at Hereford William Fitz Osbern. Using these three towns, at each of which a strong castle was erected, as bases of operations, the earls, in the course of the next fifty years, advanced step by step into the country. Their object was to possess themselves of all the level and fertile land; and their method of conquest was the castle. Opposition to them was always fierce, but seldom united or well advised. The three original barons were soon joined by others; and ere long chains of fortresses stretched out from Shrewsbury, Chester, Hereford, Gloucester, and Cardiff. The English border was thereby studded with them; and so was the whole of South Wales from Gloucester and Hereford to Pembroke and Aberystwyth. They brought with them traders, architects, and craftsmen; and a numerous colony of Flemings made Pembrokeshire their home. At the end of this period of advance it was recognized that to the Normans belonged the Marches, the fertile plains, {68} and the eastern and southern slopes of the mountains; while the rest--a land of dizzy peaks, narrow valleys, and bleak moorland--remained in the hands of the Welsh people.