Fulk of Nevers known as Foulques l'Oison (meaning the Goose, the Fool, or the Idiot), was the count of Vendôme from 1028 until his expulsion in 1032 and again from 1056 to his death. He was the second son of Bodon of Nevers and Adela of Anjou.

In 1028, his elder brother, Bouchard II, died and their mother took up the regency for the young Fulk. Half of the county was entrusted to Fulk's care. Unsatisfied, Fulk sought to evict his mother from her half. Adela gave her share to Geoffrey Martel, Count of Anjou. Martel was not long in seizing the whole country. This state continued until 1056, when King Henry I

Henry I of France

Henry I was King of France from 1031 to his death. The royal demesne of France reached its smallest size during his reign, and for this reason he is often seen as emblematic of the weakness of the early Capetians...

 ordered Martel to return the county of Vendôme to Fulk. Fulk was thereafter under the suzerainty of the counts of Anjou.

In his final decade as count, Fulk entered into war with Theobald III of Blois and with the Trinity Abbey, Vendôme.

He was married to Petronilla of Château-Gontier. They had a son and two daughters:

• Bouchard III, succeeded in Vendôme
• Euphrosine, married Geoffrey III of Preuilly
  Geoffrey II of Vendôme
  Geoffrey II, surnamed Jordan, was the lord of Preuilly from 1067 and count of Vendôme from 1085, the son of Geoffrey II of Preuilly and Almodis of Blois....
  
  
• Agatha, married Ralph Payen, viscount of Vendôme