Darood didn't call their clan Jabarti, as far i'm aware.
And yes Ismail Al-Jabarti was a real saint from Somalia that carried the nisba of the region he came from , it is pretty much recorded in the Yemeni records.
Jabarti was a nationality/regional name that Somalis in general carried irregardless of clan, it was still being used by some more isolated ones until the early 1800s, but was beginning to be fully replaced with 'Al-Somal' from the 1700s and from then on the name began to be associated with Swahili slaves we exported and ethiopians like trigrayans we converted, which i believe contributed to it's abandonement prolly in our attempt to dissociate.
Richard Burton comments on it briefly:
It's pretty clear there was an early gradually political and cultural expansion from Zayla that began in the 800s and the jabart was a refrence to the guban plains(burning country) between Zayla and Berbera, its how Somali clans were incorporated into the Aqili lineage structure.
Zayla was such a prominent Muslim town that it produced a Hadith narrators in mid 800s
Ibrahim ibn Abdullah ibn Muhammad Al Zayla’i Al Askari. Since his Sheikh died in 856 A.D. (245 A.H.) I’m Assuming he would have to have been born by 830. He, Al Daraqutni, and Al Tabari (RA) studied under the same Sheikh.
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