This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
Brigham Young had led the Latter-day Saints since Joseph Smith's murder in 1844, and after organising the exiled church at Winter Quarters he sent a vanguard company of one hundred forty eight pioneers west from there in April 1847. Advance scouts Orson Pratt and Erastus Snow entered the Salt Lake Valley on 21 July, and Young himself, delayed by illness, arrived on 24 July 1847, reportedly declaring of the barren, unclaimed valley before him, this is the place.
The pioneers began irrigating and building within days of arriving, turning a valley nobody else wanted into a functioning settlement almost immediately. That settlement became the church's new headquarters and the starting point for a rapidly growing Mormon colonization of the surrounding Great Basin, spreading outward into dozens of further towns over the following years, and the region was formally organised as Utah Territory in 1850.
What this changed for the Latter-day Saints' spread was the achievement of exactly what Missouri and Illinois had made impossible, a permanent home the church could govern on its own terms, chosen precisely because it lay far outside any existing state's reach. The pioneers' declaration on first sight of the valley became the founding claim of a Mormon homeland that has anchored the church's institutional center ever since.