Waleran de Beaumont (1104–66), the elder of the twin sons of Robert I, count of Meulan and Leicester (died 1118), was an exceptional character even among aristocrats. His sixty-two years of life spanned the reigns in England of Henry I, Stephen and Henry ii, and in France those of Louis VI and Louis VII. At the peak of his career, in the late 1130s, his estates included an English earldom focused on Worcester, much of the land between the Rivers Risle and Seine in central Normandy, control of the county of Evreux, and, across the frontier, the county of Meulan and the quarter of la Grève and Monceaux on the right bank of the city of Paris. In the later 1140s, he would add to this complex the lordship of Gournay-sur-Marne east of Paris. His estates reached from the River Trent to the Marne, and he travelled constantly across them.

The extent of Waleran's lands might be reasonably called ‘vast’: a word that otherwise tends to be overused by medievalists. The fact that his estates were spread across three distinct realms – England, Normandy and Francia – also makes them unique. Quite a number of Waleran's magnate contemporaries had lands spanning the Channel, or crossing the Norman–French border, but none cut such a swathe across three frequently competing powers. In some ways this situation assisted Waleran's political ambitions, though in other ways it was dangerous for him.