More references on the "Lost Tribes":
1:315, History of the Church, the Prophet Joseph Smith said: "...now I am prepared to say by the authority of Jesus Christ, that not many years shall pass away before the United States shall present such a scene of bloodshed as has not a parallel in the history of our nation; pestilence, hail, famine, and earthquake will sweep the wicked of this generation from off the face of this land, to open and prepare the way for the return of the lost tribes of Israel from the north country."
John Whitmer said: "The Spirit of the Lord fell upon Joseph in an unusual manner, and he Prophesied that John the Revelator was then among the Ten Tribes of Israel who had been led away by Shalmanezer, king of Assyria, to prepare them for their return from their long dispersion, to again possess the land of their fathers."
As per Revelation 10:11
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