Morianton led the people of the land of Morianton, which bore his name and lay on the seashore borders next to the land of Lehi. His uprising broke a period of peace among the Nephites under Captain Moroni, which the record calls the happiest time among the people of Nephi since the days of Nephi (Alma 50:23). Around 68 BC, in the twenty-fourth year of the reign of the judges, the people of Morianton claimed part of the land of Lehi and took up arms against its inhabitants, determined to slay them (Alma 50:25-27). The people of Lehi fled to the camp of Moroni and appealed for help (Alma 50:27).
Fearing that Moroni’s army would come against them, Morianton planned to flee with his people to the land northward and take possession of it (Alma 50:28-29). The plan was exposed when Morianton, a man of much passion, beat one of his maid servants; she fled to Moroni’s camp and told him of the people’s intentions (Alma 50:30-31). Moroni, concerned that Morianton’s people might draw others to unite with them and threaten Nephite liberty, sent an army to stop their flight northward (Alma 50:32-33).
The army, led by Teancum, headed off Morianton’s people at the narrow pass by the sea near the borders of the land Desolation (Alma 50:34). In the battle that followed, Teancum slew Morianton, defeated his army, and took the people prisoner. On covenanting to keep the peace, they were restored to the land of Morianton and joined with the people of Lehi (Alma 50:35-36).