He fell ill from sheer fatigue whilst crossing Asia Minor, and was obliged to be carried in a litter by four negroes.

"Go and tell them at home," said he to a Norman pilgrim he met returning from the Holy Land, "that you saw me being carried to Paradise by four devils." On arriving at Jerusalem, where he was received with great attention by the Mussulman emir in command there, he discharged himself of his pious vow, and took the road back to Europe.
But he was poisoned, by whom or for what motive is not clearly known, at Nicaea, in Bithynia, where he was buried in the basilica of St.Mary--an honor, says the chronicle, which had never been accorded to anybody.
From 1025 to 1042, during William's minority, Normandy was a prey to the robber-like ambition, the local quarrels, and the turbulent and brutal passions of a host of petty castle-holders, nearly always at war, either amongst themselves or with the young chieftain whose power they did not fear, and whose rights they disputed.

In vain did Duke Alain of Brittany, in his capacity as regent appointed by Duke Robert, attempt to re-establish order; and just when he seemed on the road to success he was poisoned by those who could not succeed in beating him.

Henry I., king of France, being ill-disposed at bottom towards his Norman neighbors and their young duke, for all that he had acknowledged him, profited by this anarchy to filch from him certain portions of territory.

Attacks without warning, fearful murders, implacable vengeance, and sanguinary disturbances in the towns, were evils which became common, and spread.
The clergy strove with courageous perseverance against the vices and crimes of the period.