Adela, the daughter of William the Conqueror and Matilda of Flanders, was born in Normandy in about 1062. In 1080 she married Stephen, the Count of Blois. A capable administrator, she is believed to have played a major role in managing her husband's lands.

When her husband went on the First Crusade in 1096, Adela became regent of Blois and Chartres. The Count of Blois deserted at Antioch in 1098. Adela was furious and in 1101 managed to persuade him to return to the Holy Land. He was killed the following year in Ramlah.

Adela ruled Blois and Chartes until 1107 when she handed over power to her son Theobald. Another son, Stephen of Blois, became king of England in 1136. A third son, Henry, became Bishop of Winchester. Adela died in 1137.