He seems to have been involved in his father's fall from ducal [Duke Richard II of Normandy] favour, for at much the same time as his father Ralph was fighting in Italy about 1020, Roger may be traced to Spain where he entered the service of the Countess Ermesenda of Barcelona, recently widowed and governing the county as regent for her young son. Roger was employed in defending her principality against its Muslim neighbours, especially Mujahid of the taifa kingdom of Denia, and acquitted himself well. Legends about his exploits there quickly grew up. Within at most 15 years, it was said that he had hastened the submission of his enemies by perpetrating acts of cannibalism upon his Muslim prisoners of war. Whatever the truth behind this fantastic story, Roger became notorious for his Spanish adventures: he was known in Normandy as 'Roger the Spaniard'. Reconciled with the ducal family, he returned to Normandy early in the 1030s. His foundation of the abbey of Conches in about 1035 was made possible at least in part by the wealth he had accumulated in Spain. Roger did not long survive his return. He was killed in 1040 in the course of a feud with a neighbouring family, the Beaumonts.

With his father, he was given partial custody of the castle of Tillieres in 1013/14. He was the banner bearer of all Normandy. He founded the abbey of Conches in 1035. While Duke Robert was away on pilgrimage, Roger went to Spain and had a distinguished career fighting the infidel there. While in Spain, he married, but left her behind when, due to the treachery of some of the natives, he had to leave Spain. When he returned to Normandy, he was furious to learn that the boy William had succeeded his father as Duke, declaring that a bastard ought not rule over him and other Normans. Roger immediately rebelled, ravaging the lands of his neighbors - particularly those of Humphrey de Vielles. Humphrey's son, Roger de Beaumont killed Roger and two of his sons in battle in 1038/9.