One of them, listed among tribes of the Caucasus, Pontic steppe and the Caspian region, was the "Brutakhi, who are Jews.
However, earlier in the same list Giovanni refers to "Comania", leading some to regard the postulated comma as redundant and therefore highly suspect.
[1] Some historians have theorized that the Brutakhi may have been a remnant of the Khazar people, or a result of some sort of missionary efforts.
Another possibility is that the Brutakhi are connected to the Mountain Jews of Daghestan, who are believed to have ruled independent states at points in their history.
[6] Some scholars have speculated that "Brutakhi" may be a corruption of "Brutas" or "Burtas", a steppe tribe of uncertain ethnic affiliation mentioned by other medieval sources.