Guillaume I, count of Périgord

http://genealogics.org/getperson.php?personID=I00140028&tree=LEO

The county of Périgord, named after the Celtic tribe of the Petrocorii, was located to the south-east of the county of Angoulême and now forms the major part of the département of Dordogne in France. The counts were vassals of the dukes of Aquitaine. The main towns in the county were Périgueux (ancient Vesunna) and Bergerac. From an ecclesiastical point of view, the county's territory was co-extensive with the episcopacy of Périgueux, within the archbishopric of Bordeaux. The earliest reference to Périgord as a separate county dates to 866, when Vulgrin, a member of a prominent Frankish noble family of Carolingian descent through the female line, was installed by Charles II "le Chauve" King of the West Franks as comte in Périgord and Angoulême after the death of Emenon Comte de Poitiers, as reported in the Chronicle of Adémar de Chabannes[81]. The county of Périgord was inherited by Vulgrin's younger son Guillaume, whose descendants are set out in Part A of this Chapter 2. The line of Guillaume was in constant rivalry with the descendants of Vulgrin's older son Alduin, who inherited the county of Angoulême, the latter county also falling to Bernard Comte de Périgord in [945]. Comte Bernard is reported as having eight sons, none of whom appear to have left any descendants.

The counties of Angoulême and Périgord are recorded from the mid-9th century. The Chronicle of Adémar de Chabannes and the Chronicle of Saint-Maxence both state that the counties formed part of the territories of Emenon Comte de Poitou, and that Charles II "le Chauve" King of the West Franks granted them to his relative Vulgrin after Emenon died in 866[5]. Angoulême passed to Vulgrin's older son Alduin, whose male line descendants continued to rule the county until 1202. Périgord was inherited by Vulgrin's younger son Guillaume, although during the period [945]-975 the younger line successfully challenged the older branch's control over Angoulême. The last recorded count of Périgord, who descended from count Guillaume, died in the early 12th century. After this date, the county was inherited by a younger branch of the comtes de la Marche who continued to rule as counts until the end of the 14th century.

from http://fmg.ac/Projects/MedLands/ANGOULEME.htm#_Toc167450587