Verse 22 wraps up this prophecy with a strong declaration of the eventual victory of God: "And all flesh shall know that I, the Lord [Jehovah], am thy Savior and thy Redeemer, the Might One of Jacob." There will be one shepherd who will reign in dominion and might and power and great glory. This final theme is introduced at the very end of 1 Nephi 21 (cf. Isaiah 49). Isaiah had prophesied that Israel will be restored and that they who oppress the righteous shall be "drunken with their own blood" (v. 26). We know, then, that the bad guys are going to be subdued. We know that God is going to win. That is where Isaiah leaves off in Isaiah 49, and Nephi thus picks right up with that optimistic point as he continues his own teachings and prophecy through the end in chapter 22, his closing chapter in 1 Nephi. And in the end, "all flesh shall know that I, the Lord, am thy Savior and thy Redeemer, the Mighty One of Jacob" (v. 26). That is the ultimate victory which, again, Nephi had prophesied about in 1 Nephi 14.
Book of Mormon Central, "What is the Day of the Gentiles? (1 Nephi 21:22)," KnoWhy 44 (March 1, 2016).