Gentiles are those who are not of Jewish descent or who did not come from the Jewish people. The term covers nations and peoples outside the house of Israel, and was used by the descendants of Jacob for those outside the Israelite community (Genesis 10:5). As tribal identities blurred through conquest and migration, including the Assyrian captivity of the kingdom of Israel, “Jews” came to name the Israelites remaining in the Holy Land, whether or not their lineage traced directly to Judah.
The record keeps a standing distinction between Jews and Gentiles. The risen Messiah was to show himself first to the Jews and then to the Gentiles, manifesting himself “by the Holy Ghost, unto the Gentiles” after his resurrection (1 Nephi 10:11). The conversion of the Gentiles through the preaching of the Jews was also foretold (3 Nephi 15:22).
In the last days the gospel was to come from a Gentile nation, understood to be the United States, and go to all nations. Joseph Smith, who brought forth the Book of Mormon, is identified as a literal descendant of Israel through the tribe of Ephraim (Title Page of the Book of Mormon). On this view the Gentiles are not only non-Israelites but lost Israelites to be gathered. If the Gentiles hearken to the Lamb of God, their stumbling blocks will be taken away and they will be numbered among the house of Israel (1 Nephi 14:1-2).