William Adelin Duke of Normandy

Do not confuse with his half brothers:

1. William de Tracey, son of Henry I & Gieva de Tracy.

2. William, son of Henry I & Sybil Corbet.

From WIkipedia:

William (1103–25 November 1120), surnamed Adelin (alternately rendered as Adelinus, Adelingus, Audelin or Ætheling) was the eldest son and heir of Henry I of England and his wife Matilda of Scotland. His death and that of his brother caused a succession crisis, culminating in The Anarchy.

[NB: "Atheling" is NOT as WIkipedia states a surname. It means 'Prince']

William was born in Winchester. His father, Henry I of England, was the youngest son of William the Conqueror, King of England and Duke of Normandy, and Matilda of Flanders. Robert Curthose, the eldest son of the Conqueror, had inherited Normandy, while William Rufus, one of Robert's younger brothers, had inherited England. In 1100, William was killed in a hunting accident, and Henry took the throne. By 1105, he had also dispossessed Robert of Normandy.

William's mother was Matilda (also called Edith), the daughter of Malcolm III of Scotland by Saint Margaret of Scotland. Henry had arranged the marriage to conciliate his Anglo-Saxon subjects: Saint Margaret had been a granddaughter of the Anglo-Saxon King Edmund Ironside, and a great-niece of Edward the Confessor; as such, the marriage represented a union between the new Norman rulers of England and the old Anglo-Saxon dynasty.

Henry's hopes for his succession rested upon William, who was, according to Henry of Huntingdon, "a prince so pampered" that he seemed "destined to be food for the fire." [2]

Duke of Normandy

During his lifetime, William was invested as Duke of Normandy, a title he held more in name than practice. The investiture had been made by Henry I when he was pressed by the King of France to do homage as Duke of Normandy. As a King in his own right, Henry was loath to comply, and in 1115 he offered to have William do this in his stead. This offer was eventually accepted in 1120, after an intervening period of war, and William did homage to Louis VI of France in the middle of 1120. For this reason William is sometimes counted as Duke of Normandy (as either William III or William IV – William Clito is also sometimes designated 'Duke of Normandy'). William received, as the heir to the throne, the homage and fealty of the barons of Normandy in 1115 and of the barons of England in March 1116.

William's mother Queen Edith usually served as Henry's regent in England while he was away in Normandy. After her death in 1118 William was old enough to serve in her stead. He was closely advised in this role by the King's administrators, such as Roger of Salisbury. During the last year or so of his life he was sometimes referred to as rex designatus (king designate).

During his long reign Henry I of England would face several eruptions of hostilities due to the alliances of rival regions with some of his neighbours. In order to secure the loyalty of Anjou, a long-time rival of Normandy, Henry betrothed William to Matilda of Anjou, eldest daughter of Count Fulk V of Anjou in February 1113 near Alençon.The marriage finally took place June 1119 in Lisieux.

Death

William died in the White Ship tragedy of 25 November 1120. The Prince and his companions had been crossing the English Channel from Barfleur in the White Ship, the swiftest and most modern ship in the royal fleet. William and his party had remained drinking on the shore until after dark, confident that in a fast ship and on the still sea the delay would have no real effect. Consequently, it was the middle of the night when the drunken helmsman rammed the ship into a rock in the bay. The crew and passengers were unable to lever the ship off the rock, or prevent the ship from filling with water; however, William and several of his friends managed to launch a life-dinghy. At the last minute, William dashed back to rescue his illegitimate half-sister, the Countess of Perche; when they and several others threw themselves into the small dinghy, it, "overcharged by the multitude that leapt into her, capsized and sank and buried all indiscriminately in the deep."

Henry of Huntingdon, speaking of the disaster, wrote that William, "instead of wearing embroidered robes...floated naked in the waves, and instead of ascending a lofty throne...found his grave at the bottom of the sea."

William's wife was on another ship at the time of the wreck, and survived him to become a nun and eventually, Abbess of Fontevrault.

His death ruined his father's hopes and policies. Although he made a hasty second marriage (Matilda of Scotland had died in 1118) to Adeliza of Louvain, he did not produce any more legitimate children. With no clear male heir (the obvious choice, William Clito, the son of Henry's older brother, was not favoured by the King; Henry had an abundance of other nephews and illegitimate children, of whom his favoured nephew Stephen of Blois and illegitimate son Robert of Gloucester particularly stood out, but for various reasons none were chosen), Henry designated his daughter, Matilda, dowager Holy Roman Empress, as his heiress, marrying her to William's brother-in-law Geoffrey V of Anjou, and forcing his Barons to swear to uphold her rights; but on his death, the Barons reneged on their oaths on the grounds of coercion, and chose Henry's nephew, Stephen of Blois, prompting a period of English history known as The Anarchy.