Mountain Jews are distinct from Georgian Jews of the Caucasus Mountains.
The two groups are culturally and ethnically different, speaking different languages and having many differences in customs and culture.
The Mountain Jews, or Jews of the Caucasus, are believed to have inhabited Caucasia since the 5th century CE. It is believed that they had arrived in Persia, from Ancient Israel, as early as the 8th century BCE.
Mountain Jews have an oral tradition, passed down generation after generation, that they are descended from the Ten Lost Tribes which were exiled by the king of Assyria (Ashur), who ruled over northern Iraq from Mosul (across the Tigris River from the ancient city of Nineveh).
The reference, most likely is to Shalmaneser, the King of Assyria who is mentioned in II Kings 18:9-12.According to local Jewish tradition, some 19,000 Jews departed Jerusalem (used here as a generic term for the Land of Israel) and passed through Syria, Babylonia, and Persia and then, heading north, entered into Media Mountain Jews maintained a strong military tradition.