Robert Curthose's monument at Gloucester Cathedral

Robert (called Curthose for his short squat appearance) (c. 1054 – February 10, 1134) was a Duke of Normandy. He was the eldest son of William the Conqueror and Matilda of Flanders, an unsuccessful claimant to the throne of England, and a participant in the First Crusade. His reign as Duke is noted for the discord with his brothers in England, eventually leading to the absorption of Normandy as a possession of England.

His birthdate is usually given as 1054, but may have been in 1051.

In his youth, he was reported courageous and skillful in military exercises. He was, however, also prone to a laziness and weakness of character that discontented nobles and the King of France exploited to stir discord with his father William.

In 1077, he instigated his first insurrection against his father as the result of a prank played by his younger brothers William Rufus and Henry, who had poured water through the floor into Robert's chambers. As a result of the insult, Robert attempted to seize the castle of Rouen and afterwards spent several years wandering in aimless fighting before being reconciled with his father.

In 1087, the father died, having divided the Norman dominions between his two eldest sons. To Robert, he granted the Duchy of Normandy and to William Rufus he granted the Kingdom of England. Of the two sons, Robert was considered to be much the weaker and was generally preferred by the nobles who held lands on both sides of the English Channel, since they could more easily circumvent his authority. At the time of their father's death, the two brothers made an agreement to be each other's heir. However, this peace lasted less than a year when barons joined with Robert to displace Rufus in the Rebellion of 1088. It was not a success, in part because Robert never showed up to support the English rebels.

Robert married Sybil, daughter of Geoffrey of Brindisi , Count of Conversano (and a grandniece of Robert Guiscard). Their son, William Clito, was born October 25 1102 and became heir to the Duchy of Normandy. Sybil, who was admired and often praised by the chroniclers of the time, died shortly after the birth. William of Malmesbury claims she died as a result of binding her breasts too tightly; both Robert of Torigny and Orderic Vitalis suggest she was murdered by a cabal of noblewomen led by her husband's mistress, Agnes Giffard.

Robert took as his close advisor Ranulf Flambard, who had been previously a close advisor to this father.

In 1096, Robert left for the Holy Land on the First Crusade. At the time of his departure he was reportedly so poor that he often had to stay in bed for lack of clothes. In order to raise money for the crusade, he mortaged his duchy to his brother William for the sum of 10,000 marks.

He had agreed with William II to name each other the Heir Presumptive of England and Normandy respectively. When William II died on August 2, 1100, Robert should have inherited the throne of England. But he was on his return journey from the Crusade, allowing their younger brother Henry to seize the crown of England for himself. Upon his return, Robert, urged by Flambard, lead an invasion of England to retake the crown from his brother Henry. In 1101, Robert landed at Portsmouth with his army, but his lack of popular support among the English enabled Henry resist the invasion. Robert was forced by diplomacy to renounce his claim to the English throne in the Treaty of Alton.

In 1105, however, Robert's continually stirring of discord with his brother in England prompted Henry to invade Normandy, and in the next year, Henry defeated Robert's army decisively at the Battle of Tinchebray and claimed Normandy as a possession of the English crown, a situation that endured for almost a century. Captured after the battle, Robert was imprisoned for the rest of his life.

In 1134, he died while imprisoned in Cardiff Castle. He was buried in the abbey church of St. Peter in Gloucester, where an elaborate sepulchre was later built. The church subsequently has become Gloucester Cathedral.

References

• David, Charles Wendell. Robert Curthose, Duke of Normandy. Cambridge, Mass. : Harvard University, 1920.
• Green, Judith. "Robert Curthose Reassessed". Anglo-Norman Studies, 22 (1999).
• Mooers, Stephanie L. " 'Backers and Stabbers' : Problems of Loyalty in Robert Curthose's Entourage". Journal of British Studies, 21.1 (1981): 1-17.