Just to be clear. WEST of the Jordan is biblical Israel, although the Reubenites and half tribe of Manasseh occupied much of the east bank. They were exiled by the Assyrians and carried away to northern Syria, Iraq, perhaps western Afghan as well, although that’s uncertain.
Menasseh has been found, and quite a few of them are now living in Kiryat Arba. They were in Northeastern, rural India, among the Kuci tribe, and their features are now very Asiatic, after a sojourn in China and some persecution there.