Guillaume I, II. vicomte de Marseille

His father was  "Arlulfe of Marseille" not Pons 

 https://fr.wikipedia.org/wiki/Arlulfe_de_Marseille

https://fr.wikipedia.org/wiki/Guillaume_I_de_Marseille Guillaume I of Marseille

https://fr.wikipedia.org/wiki/Vicomtes_de_Marseille Viscounts of Marseille

The first known ancestor of this family is Arlulf of Marseilles or Arlulfe 2 which appears on the occasion of the donations of the fiscal lands and the public rights of the valley of Trets which it benefits in 950 from the king of Burgundy-Provence Conrad III of Burgundy 3 . For the historian Jean-Pierre Poly , most of the Marseille tax authorities were given by King Conrad to Arnulf the Viennese son of Thibert, around the years 948 - 952 4. This is a huge area, about 60,000 hectares, which far exceeds the boundaries of the Trets area. Arlulf receives not only curtis , but in addition, the exercise and the profit of all the public rights attached, in other words the seigneurial ban 5 .

According to the hypothesis of G. de Manteyer taken by JP Poly , Arlulf would be the grandson of Count Teutebert , also called Thibert who had administered the Kingdom of Provence on behalf of King Louis III the Blind in the 890s - 908 . It belongs therefore to the Frankish nobility settled in the Bas-Rhone countries during the Carolingian era and more probably to that of the Viennese coming from Hugues d'Arles who was able to free himself from the aristocratic clan of the Bosonides for perpetuate its roots in Provencefollowing the death of Hugues and the disgrace or absence of his nephew, the archbishop of Arles Manasses .

His son, Guillaume de Marseille , marries Belielde.

Child marriage of their two children [unclear] is an exception in the Provence of the x th century . Backlash violent political unrest oppose early x th century the Burgundians , from the north, as Arlulf Marseille and local, as Pons Marseille . The confrontation turns into a clash of cultures: partisans and opponents of the Frankish invaders fight with anthroponyms. The first, such as Châteaurenard or Agoult who proclaim themselves salicthe Sabran, the Reillane, or the Lacoste reject the old senatorial names; the latter cling to it, like the Viscounts of Marseilles (qualified of novels), the Mévouillon or Castellane. If a little less than a fifth of the names of the great Provencal families remains Gallo-Roman between 950 and 1020 , it is carried by only four families, who refuse the Burgundians . Nevertheless even Pons de Marseille , despite his first name, Poncius, is certainly of Germanic origin......etc

Occupation: Count of Marseille

• House Of Baux