Robert Curthose

Robert Curthose (–1134), sometimes styled Robert II or Robert III, was the Duke of Normandy from 1087 until 1106. He was also Count of Maine. His reign as Duke is noted for the conflicts he had with his brothers in England. This led to the dukedom of Normandy being reunited with crown of England.
Early career.
Robert was the eldest son of William the Conqueror, the first Norman king of England, and Matilda of Flanders. Robert was born . As a child he was to Margaret, the heiress of Maine. But she died before they could be wed. Robert didn't marry until he was in his late forties.
Robert was brought up among William's . As a result, he became a skilled warrior. But unlike his father he expected to live a life of pleasure and luxury. In 1063, his father made him the count of Maine when he was contracted to marry Margaret. But Robert had no authority. The county was actually run by his father until 1069 when the county revolted and reverted to Hugh V of Maine. Still, he had been made his father's heir. Twice the barons had taken an oath of fealty to him as their future leader.
In 1077 Robert got into an argument with his father. He demanded to rule Normandy which he had on at least on occasion while William was in England. William was not able to reason with his son and Robert left angry. The next day Robert and his followers attempted to seize Rouen. The siege failed. After rebelling against his father all he could do was go into exile. 
Robert first went to Chateauneuf-en-Thymerais. He then fled to Flanders to the court of his uncle Robert I, Count of Flanders. 
In the spring of 1080 Robert was back on good terms with his father. He again made Robert his heir for Normandy in the presences of his barons. Later that summer or early fall Robert went with his father to England. William placed Robert in charge of a large army to march north and deal with King Malcolm III of Scotland. Malcolm had been raiding the north of England while William was occupied in Normandy. When the two armies drew near each other, Malcolm did not want to fight. He again swore fealty to king William and gave hostages. Robert remained in England with his father until the end of 1081. Events in Maine caused William and Robert to return to Normandy. Fulk IV, Count of Anjou had been attacking in Maine again trying to get control away from Normandy. William and Robert led a great army into Maine to confront the Angevin count. Before the fighting could start, a cardinal and several monks stopped the battle. They called for a truce and after much negotiation one was agreed to. The count of Anjou was to let Normandy have Maine, but Robert, as count of Maine, had to recognize Fulk IV as his overlord for Maine. When Queen Matilda died in 1083 Robert seemed to abandon his father. He and his mother had been very close. 
In 1087, the Conqueror died of wounds suffered from a riding accident during a siege of Mantes. At his death he reportedly wanted to disinherit his eldest son but was persuaded to divide 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. The youngest son Henry was given money to buy land. Of the two elder 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 took as his close adviser Ranulf Flambard, who had been previously a close adviser to his father. Flambard later became an astute but much-disliked financial adviser to William Rufus until the latter's death in 1100.
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 mortgaged his duchy to his brother William for the sum of 10,000 marks.
When William II died on 2 August 1100, Robert was on his return journey from the Crusade and was about to marry a wealthy young bride to raise funds to buy back his duchy. As a result, his brother Henry was able to seize the crown of England for himself. Upon his return, Robert – urged by Flambard and several Anglo-Norman barons – claimed the English crown on the basis of the short-lived agreement of 1087. In 1101, he led an invasion to oust his brother Henry; he landed at Portsmouth with his army but his lack of popular support among the English as well as Robert's own mishandling of the invasion tactics enabled Henry to resist the invasion. Robert was forced by diplomacy to renounce his claim to the English throne in the Treaty of Alton. It is said that Robert was a brilliant field commander but a terrible general in the First Crusade. His government (or misgovernment) of Normandy as well as his failed invasion of England suggests that his military skills were little better than his political skills.
In 1105, however, Robert's continual stirring of discord with his brother in England as well as civil disorder in Normandy itself prompted Henry to invade Normandy. Orderic reports on an incident at Easter 1105 when Robert was supposed to hear a sermon by the venerable Serlo, Bishop of Sées. Robert spent the night before sporting with harlots and jesters and while he lay in bed sleeping off his drunkenness his unworthy friends stole his clothes. He awoke to find himself naked and had to remain in bed and missed the sermon.
In 1106, 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 in Devizes Castle for twenty years before being moved to Cardiff.
In 1134, Robert died in Cardiff Castle in his early eighties. Robert Curthose, sometime Duke of Normandy, eldest son of the Conqueror, was buried in the abbey church of St. Peter in Gloucester. The exact place of his burial is difficult to establish – legend states that he requested to be buried before the High Altar. His effigy carved in bog oak, however, lies on a mortuary chest decorated with the attributed arms of the Nine Worthies (missing one – Joshua, and replaced with the arms of Edward the Confessor). The effigy dates from about 100 years after his death and the mortuary chest much later. The church subsequently has become Gloucester Cathedral.
Family.
Robert married Sybilla of Conversano, daughter of Geoffrey of Brindisi, Count of Conversano (and a grandniece of Robert Guiscard, another Norman duke) on the way back from Crusade, one child:
Robert also had at least three illegitimate children: