Noahite Gnostics in the Roman Province of Tachkastan followed the Essene Jews from whom the Manicheans had seceded from them under the influence of Marcionism and Mandaeism.
Noahite Gnostics did not consider themselves Arabs (9:97) but spoke Quraysh, an Arabic dialect influenced by Imperial Aramaic which they called Intelligible Arabic (16:103) to distinguish it from the common Quraysh language spoken by Muslim Arabs (49:14).
They were commonly Gnostic Zera-Israel who rejected any Nasrani and Hindu claims to Abraham.