The Ten Lost Tribes were the ten of the Twelve Tribes of Israel that were said to have been exiled from the Kingdom of Israel after its conquest by the Neo-Assyrian Empire c. 722 BCE. These are the tribes of Reuben, Simeon, Dan, Naphtali, Gad, Asher, Issachar, Zebulun, Manasseh, and Ephraim; all but Judah and Benjamin (as well as some members of Levi, the priestly tribe, which did not have its own territory). However, since the tribe of Simeon lived well within the territory of Judah, it is not clear as to why this tribe was never included in this list (or as a part of the northern kingdom of the 10 tribes). Also, the tribes of Asher and Reuben were never mentioned as participating in anything after the conquest, living in either Phoenician (Asher) or Moabite (Reuben) controlled territory. By the middle 9th century BCE the territory of Gad was also (re)taken by the Moabites (see Mesha Stele), so the Assyrians could at most have removed the other six tribes. Thus, the "10 tribes" appears to be a misnomer, meaning that all of the Jews were living outside the Kingdom of Judah. The Jewish historian Josephus (37–100 CE) wrote that "there are but two tribes in Asia and Europe subject to the Romans, while the ten tribes are beyond Euphrates till now, and are an immense multitude, and not to be estimated by numbers".

In the 7th and 8th centuries CE, the return of the lost tribes was associated with the concept of the coming of the messiah.^: 58–62 Claims of descent from the "lost tribes" have been proposed in relation to many groups, and some religions espouse a messianic view that the tribes will return.

Historians have generally concluded that the deported tribes assimilated into the local population, and some of those Israelites who remained formed the Samaritan community. However, this has not stopped various religions from asserting that some survived as distinct entities. Zvi Ben-Dor Benite, a professor of Middle Eastern history, states: "The fascination with the tribes has generated, alongside ostensibly nonfictional scholarly studies, a massive body of fictional literature and folktale."^: 11 Anthropologist Shalva Weil has documented various differing tribes and peoples claiming affiliation to the Lost Tribes throughout the world.