Duke of Chartres

Originally, the Duchy of Chartres (duché de Chartres) was the comté de Chartres, a County. The title of comte de Chartres thus became duc de Chartres. This duchy–peerage was given by Louis XIV of France to his nephew, Philippe II d'Orléans, at his birth in 1674. Philippe II was the younger son and heir of the king's brother, Philippe de France, Duke of Orléans.

The northern portion of the County of Blois, bordering on Normandy, was sometimes alienated as the County of Chartres, but the Counts of Blois who possessed it did not use a separate title for it. In 1391, the death of the only son of Guy II, Count of Blois prompted him to sell the inheritance of the County of Blois to Louis of Valois, Duke of Orléans, merging the title into the royal dukedom.

960-975 Theobald I of Blois († 975), Count of Blois and Chartres, which he took in 960

975-995 Odo I, Count of Blois, († 995), Count Chartres, and Reims Count (982-995), son of the previous

995-1004 Thibaut II († 1004), Count of Blois, Chartres and Reims, the son of the previous

1004-1023 Eudes II of Blois († 1037), Count of Blois, Chartres, Reims, de Meaux and Troyes, brother of the previous

1037-1089 Theobald III, Count of Blois (1019 † 1089), Count of Blois, Chartres, Meaux and Troyes son of Eudes II and Ermengearde d'Auvergne

1089-1102 Stephen II, Count of Blois († 1102), Count of Blois, Chartres and Meaux, son of Thibaut III and Gersende of Maine.

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