The exile of the Israelites in the provinces of the Assyrian Empire.
In 734 B.C. Theglathphalasar III conquered Israel and deported many of the leading Israelites to Assyria (4 Kings 15).
Twelve years later (722 B.C.), Sargon destroyed Samaria, and carried off the upper classes to Mesopotamia and Media (4 Kings 17; 1 Par. 5).
The Book of Tobias gives a glimpse of the lot of these exiles, who on the whole enjoyed a considerable amount of liberty, but were at times subjected to persecution (Tobias 1).
There is no record of their return to Palestine.
New Catholic Dictionary