The County of Châteaudun was held in the 9th century by counts who also held the County of Blois. Theobald I created the first viscount of Châteaudun with the appointment of Geoffrey I, founder of the House of Châteaudun. The viscounts were entrusted with the government of the county of Châteaudun, records of whom are continuous from the mid-10th century. The actual rule of Châteaudun between the late 9th and the mid-10th centuries, and the relationships between the count and viscounts, is uncertain. The county was revived in 1439 when the region was recreated as the County of Dunois and granted to Jean Levieux Valois des Orléans (Jean de Dunois), the illegitimate son of Louis I, Duke of Orléans, son of Charles V of France. Châteaudun is closely associated with the County of Perche and the early rulers generally held both titles of viscount of Châteaudun and count of Perche. There are also close ties between these counts and the counts of Anjou, and members of the House of Ingelger and House of Plantagenet descended from this line. The family tree of the House of Châteaudun is most illustrative of these relationships. The following lineage shows the counts of Châteaudun, the viscounts of Châteaudun, and the related counts of Perche and Anjou. Dates shown are the approximate dates of rule. Counts of Châteaudun The following are the known counts of Châteaudun: William (through 834), also count of Blois, reportedly killed by Hastein, Viking chieftain and compatriot of Björn Ironside, son of Ragnar Lothbrok. Odo I (834–871), brother of Robert the Strong (count of Anjou), also count of Troyes, Anjou and Blois. Odo II (871–886), son of the previous, also count of Troyes Robert I (through 886), son of the previous, also count of Troyes Adalelm (886–894), nephew of the previous, also count of Troyes. The period between Adalelm and Theobald is uncertain, but may have been filled by Counts Warnelad and Gello. Theobald the Trickster (through 975), also count of Blois and Chartres Odo I (975–996), son of the previous, also count of Blois and Chartres Theobald II (996–1004), son of the previous and stepson of Robert the Pious, also count of Blois and Chartres Odo II (1004–1037), brother of the previous, also count of Troyes, Blois, Chartres, Beauvais and Tours. Viscounts of Châteaudun The position of viscount of Châteaudun was created by Theobald I in 967. As noted above