Thibault (Thibaud) III DE BLOIS Comte de Chartres, de Châteaudun..
- Born: Bef 1012, Mormontier, France
- Married (2): Bef 1061
- Died: 30 Sep 1089, Epernay, Brittany, France
Comte de Chartres, de Châteaudun, de Meaux, de Sancerre et de Troyes
Theobald inherited amongst others the counties of Blois, Tours, Chartres. Chateaudun and Sancerre, and also in Champagne: Chateau-Thierry, Provins and St. Florentin. His brother Stephen inherited the counties of Meaux, Troyes and Vitry.
Theobald conspired against the king of France Henry I, was beaten in 1044 and had to give up the county of Tours to regain his freedom. From then on the centre of power for the House of Blois moved to Champagne. Theobald found ways to become close to the royal court again and gain infuence. He got the title of Count Palatine, which his father had used before. He used this influence to get control over his brother's possessions in Champagne that were inherited by his minor nephew Odo III. Odo later joined the army of William the Conqueror, participated in the battle of Hastings, married a sister of William and became count of Aumale and Holderness.
Theobald had a position of considerable power, that increased when he married the daughter of Raoul de Valois. From 1074 onward, he left his son Henry in control of Blois, Chateaudun and Chartres.
Thibault married Gersinde (Gersende) DU MAINE, daughter of Herbert I "Eveille-Chien" DU MAINE and Paule DE PREUILLY.
Thibault also married Alix DE CRÉPY comtesse de Bar-sur-Aube, daughter of Cte Raoul III "Le Grand" DE VEXIN comte de Valois et Vexin and Ctse Adèle DE BAR-SUR-AUBE, before 1061.