There is nothing in the sources to make us believe that the Muslims in the Muslim town of Ghana were anything else besides Soninke. The Royal elite of Medieval Ghana took a conscious decision not to adopt Islam. Neighbouring kingdoms such as Gao, whose trading and commercial networks were part of the Wangara trading networks did the opposite. Wangara is the name given to the network of Soninke Islamic merchants, who would have been the Muslims and merchants occupying the Islamic section of Koumbi Saleh. These Soninke merchants were also reported to be occupying predominantly Berber towns further north in the Sahara. They were the ones who brought Islam to Gao in the 10th century (which is almost contemporary or rather a little earlier with your quote from Al Bakri about Ghana).
It's hard to imagine that Wangara Islamic trading networks would be advanced enough to reach and influence Gao and yet a Soninke king would be relying on Maghrebis or foreigners as elites in his royal court or commercial capital . Here is a description of Gao, writen by Muhallabi in 990 ad. Your quote if I am not mistaken is from Al Bakri, written in 1068 ad:
.... a town on the Nile [Niger], on the eastern bank, which is called Sarnah
[Gao-Saney], where there are markets and trading houses and to which there
is continuous traffic from all parts. He has another town to the west of the
Nile where he and his men and those who have his confidence live. There is a
mosque there where he prays but the communal prayer-ground is between the
two towns. In his own town he has a palace which nobody inhabits with him
or has resort to except a eunuch slave. They are all Muslims. The costume of
their king and his chief companions consists of shirts and turbans. They ride
horses bareback. His kingdom is populous…. The wealth of the people of
his country consists of livestock. The king’s treasure-houses are spacious, his
treasure consisting principally of salt (Levtzion and Hopkins : ).
You can see that the king of Gao elected to be a Muslim and his royal court contained Muslims as well. It had nothing to do with ethnicity. The king of Ghana was simply particular about preserving the distinction between the traditional religion and the new religion of Islam.
Interesting. I did not know Islam already had such a foothold in the Western Sudan that early, but it makes sense considering the trading networks of the Wangara and Jula spread Islam as far away as the forest basin and hausaland. Would any of the muslims in kumbi saleh be from Tekrur? Wasn't Tekrur the first kingdom in the Sudan to adopt Islam?
You should take a note from mansa, he's actually able to explain things without sounding rude or condescending. Why bump a thread that is almost two years old only to accuse me of spreading nonsense and being stupid? You're pathetic.
I interpreted the separation as being along racial lines rather than purely religious. I'm no scholar on ancient ghana or al-bakri and I certainly never stated that I was. This is a history forum, it's purpose is for posters to discuss history and see what they can learn from texts, archaeology and more knowledgeable posters.