Some minor biographical details can be found here: https://www.encyclopedia.com/religion/encyclopedias-almanacs-transc...
Does not correspond to the genealogy listed here.
I'm not sure all of his mess was fabricated by him.
I think he copied a lot of material out of Arthur J. Zuckerman's largely discredited book - https://en.wikipedia.org/wiki/A_Jewish_Princedom_in_Feudal_France
Ugh. The rot has spread to the wikipedia article on R Gershom as well now.
The sources I'm looking at all say that there's very little biographical detail of his life at all.
* https://www.encyclopedia.com/religion/encyclopedias-almanacs-transc...
* https://biography.yourdictionary.com/gershom-ben-judah
* http://jewishencyclopedia.com/articles/6615-gershom-ben-judah
Private User Joshua Lipson I agree with you both. Isaac the Jew's, ancestry is incredibly dubious at best. I fixed several Wikipedia pages and the Geni profile for his father, see [Rabbi Judah of Narbonne Judah of Narbonne]