[5][1] Henry's father died in 1102 while on crusade during the Second Battle of Ramla, leaving an estate with more than 350 castles and large properties in France including Chartres.

[1] Henry was educated at Cluny and adhered to the principles of Cluniac reform, which included a sense of intellectual freedom and humanism, as well as a high standard of devotion and discipline.

However, on 1 March 1139, during the reign of his brother Stephen, Henry obtained a commission as papal legate, which gave him higher rank than Theobald of Bec, Archbishop of Canterbury, making him the most powerful figure in the English Church during the troubled times of The Anarchy.

Later that year, Henry rejoined his brother's side and, with the help of Queen Matilda and an army commanded by William of Ypres, his successful defence of Winchester against the Empress was the turning point of the civil war.

Henry of Blois engineered hundreds of projects, including villages and canals, abbeys and smaller churches.

He also designed and built additions to many palaces and large houses including the castle of Farnham, Surrey[11] and began the construction of the Hospital of St Cross at Winchester.

He wrote or sponsored several books including On the Antiquity of the Glastonbury Church by William of Malmesbury, a close personal friend.

The expiration of Henry's legatine commission when Pope Innocent II died on 23 September 1143[4] deprived him of much of his power.

His efforts to renew the commission were unsuccessful, but he made a personal visit to Rome and secured several favours for Glastonbury and the Benedictine order in general.

Shortly after his brother's death and the accession of Henry II, the bishop retired to Cluny, where he had sent much treasure, for at least two years and mourned there his mentor Peter the Venerable, who died on Christmas Day, 1156.