Near the end of the four years of peace spoken of in verse 12, of the preceding Chapter, war was again commenced between the Nephites and the Lamanites. Notwithstanding his youth, Mormon, being large of stature, was appointed to lead the armies of the Nephites.
Mormon must have had many qualities of leadership besides being physically large, such as unusual power, or strength, ability to see and observe, quick to make decisions, honest, true and comprehensive, but above all else, he was faithful to God and His laws. He was, like the Brother of Jared, "a large and mighty man" (Ether 1:34) in personal appearance, and undoubtedly as strong in his integrity to God and in his moral courage as he was in physical characteristics. In the short autobiography he gives us, Mormon states that "three hundred and twenty-six years had passed away," since the birth of Christ, and that "in my sixteenth year I did go forth at the head of an army of the Nephites, against the Lamanites."
The next year saw disaster follow the Nephite cause. Mormon's troops retreated before the Lamanites who came against them showing great strength and resourcefulness, insomuch so that the Nephite armies were terrified when they beheld their battle array. Mormon's soldiers fled northward, and did not stop until they "did come to the City of Angola." Here the Nephites made a stubborn stand, yet in spite of the fortifications they had built, Mormon says: "The Lamanites did come upon us and did drive us out of the City." Nor did the Nephite retreat stop in the land round about Angola, but the Land of David whereunto they fled offered them no asylum. Escape from the results of their iniquity did not come to them because of repentance which they did not, for the old habits and practices of wickedness pursued them as well as the Lamanite hordes. An attempt was made by Mormon and others of their leaders to assemble all the Nephites into one place that the full strength of their numbers could be felt. With this end in view, the armies of the Nephites marched into the Land of Joshua which was on the borders of the Western Sea.