Answer :
They believed that it was their destiny to travel west and the mormon where looking for a place where they could be free from prosecution
Two reasons fueled the Manifest Destiny to the West. 1) American pride of American nationalism 2) Belief that the religion of the American people should Christianize the world. People traveled along the Oregon Trail, which was the most rugged westward trail, because they believed it was the destiny of America to conquer and own all the land from sea to sea. California already had a lot of settlers so moving north was next. The Mormons left Illinois after the people there killed their leader and wanted to go somewhere they thought they would not be bothered ever again because of their beliefs. They wanted to build a City of Zion for worship. They chose Utah because it was remote, the soil wasn't really fertile and no one else wanted it, the climate was unfriendly and others sought better weather elsewhere. Therefore, when they came to this area, Brigham Young who had taken over for John Smith, said they had gone far enough.