[1] William I was a nephew of Emenon or Amaujeu de Sabran, who was noted as the first person known in the House of Sabran who had a recorded signature in a historic document dating back to 1029.
[2] During the Battle of Antioch, Raymond IV of Toulouse decided to defend the fort of Mahomerie, then he chose his best captains to defend him: Pierre of Castillon, Raymond I of Turenne, William V of Montpellier, William I of Sabran and Gouffier of Lastours, in addition to 500 most valiant men of their troops.
During the siege of Jerusalem in July 1099, nine Genoese vessels arrived at the port of Jaffa to support the crusaders.
[4] William I would marry his cousin Adalasie Amic, daughter of Pierre Amic and Agnès of Avignon, the descendant of Louis Boson the Blind, King of Provence, and great-granddaughter of Louis the Pious and of Anne of Constantinople.
William I was known for having built the “Charterhouse of Valbonne”, which was in a forest between La Roque and Goudargues.