According to John Sorenson, as soon as Nephi became ruler over a part of Lehi's descendants, Nephi's personal record in fact became the record of his rule over the people (2 Nephi 5:33; Jacob 7:26). Thereafter his successors, consisting of direct descendants from him, continued to make entries in the growing account (Jacob 1:2-3, 9-20; Omni 1:11; Mosiah 17:2; 25:13; 28:10-11, 20; Alma 63:1; Helaman 3:37; 3 Nephi 1:2; 5:20; Mormon 1:1-5; 6:6). The record of this ruling lineage was kept on "the plates of Nephi" [Large Plates] as the official account of notable events of their reign. . . . The lineage founded by the original Nephi continued to hold the charter and sacred emblems of rulership over all Lehi's descendants. The Nephi lineage continued powerful until the fourth century A.D., when Mormon became its (final) leader (Mormon 1:5; 2:1-2). In all likelihood he was the senior male in the senior branch of the line, or he would not have been installed so easily in the crucial leadership position over his group's armies at age 15, no matter what charismatic qualities he brought to the task. [John L. Sorenson, An Ancient American Setting for the Book of Mormon, pp. 51, 163-164]