During the time of Shlomo’s son ruling Yisrael, the tribes of Yisrael split. Yuhudah and Binyamin stayed to be ruled under him. But the other 10 tribes left and where ruled by another king who they chose. In the Tanak under Kings and Chronicles, it says the lost 10 tribes were in the land where Ashuur had taken them as captives. Did the 10 tribes ever return to Yisreal as a group before 2400 years ago? Does the name Jew represent all of the 13 tribes (Yosef equals Efraim and Mannaseh) of Yisreal?
The Tanach (Bible) itself tells us that Sanhereb, king of Assyria, exiled the ten tribes more than 100 years before the destruction of the First Temple (Kings II, 17, 6, about the year 700 BCE), and since then, they have generally not been heard from (few came back in the time of Ezra, Chron. I, 9). Accordingly, most Jews today are from the tribe of Judah (hence, the name “Jew’) with a minority from Binyamin and Shimon, Judah’s neighbors. The exception are those Kohens and Levites, who lived among Judah (they always lived dispersed in 48 cities among the different tribes in Israel, because they were not allotted a portion of the Land), and therefore were not exiled with the ten tribes. They are all called “Jews” even those who technically aren’t from Judah, although “Israel” would be a more accurate term which includes us all. Interestingly, the Jews from Ethiopia have a tradition, upheld by many rabbis, that they are from Dan, which is one of the lost ten tribes. Recently, there has been an aliya to Israel of about 3,000 people from India who continued many Jewish customs, and claim a tradition that they descend from the tribe of Menasheh. Nevertheless, they must undergo conversion because they have been removed for so long from Judaism, many intermarried, etc.