In researching Matilda Lupus - only a couple of people have her occasion of death correctly. She died on the shipwreck of the Blanche Nef in 1120. Here is the story:
The Wreck of the White Ship
On the 25th November 1120 a disaster struck in the English Channel which had a dramatic effect, not only on the families of those involved, but on the very fabric of English Government. Some of the following is simply speculation, since only one man survived and he was not one of the crew and would not have known much of what took place on deck with the captain, Thomas Fitz Stephen, and the crew.
The Norman dynasty had not long established itself on the English throne and King Henry I was eager that his line should continue to wear the crown for many generations to come. Despite having numerous bastard offspring, he had but two surviving legitimate children and his hopes for his family were firmly secured by the birth of his only son, William the Aethling: called by the Saxon princely title to stress that his parents had united both Saxon and Norman Royal Houses. William was a warrior prince who, even at the age of seventeen, fought alongside his father to reassert their rights in their Norman lands on the Continent.
After the successful campaign of 1119 which culminated in King Louis VI of France's defeat and humiliation at the Battle of Brémule, King Henry and his entourage were finally preparing to return to England. Henry was offered a fine vessel, the White Ship, in which to set sail for England, but the King had already made his traveling arrangements and suggested that it would be an excellent choice for his son, William.
As the rising star of the Royal Court, Prince William attracted the cream of society to surround him. He was to be accompanied by some three hundred fellow passengers: 140 knights and 18 noblewomen; his half-brother, Richard; his half-sister, Matilda the Countess of Perche; his cousins, Stephen and Matilda of Blois; the nephew of the German Emperor Henry V; the young Earl of Chester and most of the heirs to the great estates of England and Normandy. There was a mood of celebration in the air and the Prince had wine brought aboard ship by the barrel-load to help the party go with a swing. Both passengers and crew soon became highly intoxicated: shouting abuse at one another and ejecting a group of clerics who had arrived to bless the voyage. Some passengers, including Stephen of Blois, who was ill with diarrhea, appear to have sensed further trouble and decided to take a later craft.
The onboard revelries had delayed the White Ship's departure and it only finally set out to sea, after night had already fallen. The Prince found that most of the King's forces had already left him far behind yet, as with all young rabble-rousers, he wished to be first back home. He therefore ordered the ship's master to have his oarsmen row full-pelt and overtake the rest of the fleet. Being as drunk as the rest of them, Thomas Fitz Stephen complied and the ship soon began to race through the waves.
An excellent vessel though the White Ship was, sea-faring was not as safe as it is today. Many a boat was lost on the most routine of trips and people did not travel over the water unless they really had to. With a drunken crew in charge moreover, it seems that fate had marked out the White Ship for special treatment. It hit a rock in the gloom of the night and the port-side timbers cracked wide-open to reveal a gaping whole.
Prince William's quick-thinking bodyguard immediately rushed him on deck and bundled him into a small dinghy. They were away to safety even before the crew had begun to make their abortive attempts to hook the vessel off the rocks. However, back aboard ship, the Prince could hear his half-sister calling to him, begging him not to leave her to the ravages of the merciless sea. He ordered his little boat to turn round, but the situation was hopeless. As William grew nearer once more, the White Ship began to descend beneath the waves. More and more people were in the water now and they fought desperately for the safety of the Royal dinghy. The turmoil and the weight were too much. The Prince's little boat was capsized and sank without trace.
It is said that the only person to survive the wreck to tell the tale was a Rouen butcher, called Berold, who had only been on board to collect debts owed him by the noble revellers. Finely dressed bodies, such as the Earl of Chester's, were washed up along the Norman shoreline for months after.
After King Henry heard of the disaster, it is said that he never smiled again. Desperate to secure his family's succession, he had the English barons swear an oath to uphold the rights of his only remaining legitimate child: his daughter Matilda who they were to recognize as their Queen after Henry's death. But the time had not yet come for a woman to be accepted on the English throne. When King Henry died, his nephew, Stephen of Blois seized the crown and four years later, the status quo degenerated into a patchy Civil War.