His real name is unknown, but he remembers being called Jean back when he was a slave in what now is Haiti. He was Embraced at an unspecified point and since then has only known the desire to kill and get revenge specially on his slavers (white rich people). Although he was mostly controlled by the Beast, he proved cunning enough to prioritize survival and powerful enough to survive and come ahead in most encounters.
In the mid-19th century, Jean was in New Orleans where he got the nickname Jean l'Isle to distinguish him from all the other Kindred named Jean. In 1904, his bloodlust got him exiled by the prince, so he kept moving northeast, killing the mortals he fed from and then moving on just before a Blood Hunt was called. In the mid-90s he arrived in Indiana and his unlifestyle got the attention of Sullivan Dane, whom with the help of the Inquisition burned Jean. In truth Jean managed to survive by turning to ashes, but was weak and trapped in a clay urn by Lazlo Varga who used some magic to kept him sealed there before he could recover and break free.