Sometime after "thirty years had passed away from the time [Lehi] left Jerusalem," (2 Nephi 5:28), Nephi mentions that "he had kept the records upon plates, which I had made, of my people thus far." (2 Nephi 5:29). These plates are commonly referred to as the large plates of Nephi (see 1 Nephi 9:2). Nephi then goes on to mention that, "the Lord God said unto me: Make other plates; and thou shalt engraven many things upon them which are good in my sight, for the profit of thy people" (2 Nephi 5:30). These plates are commonly referred to as the small plates of Nephi (see 1 Nephi 9:2). According to John Welch, the sequence of events in 2 Nephi 5 suggests that the small plates of Nephi were made in connection with the coronation of Nephi. Accordingly, they served as the "tablets of the law," or the pillar or stele that were traditionally set up as a monument to the creation of the new king's order. Nephi wrote on these plates things that were "good in [God's] sight, for the profit of [his] people" (2 Nephi 5:30). In addition to the religious purposes that these plates primarily served, they also acted as a founding constitutional and political document, as has been discussed by Noel Reynolds in his article "The Political Dimension in Nephi's Small Plates." [John M. Lundquist and John W. Welch, "Kingship and Temple in 2 Nephi 5-10," in Reexploring the Book of Mormon, F.A.R.M.S., p. 67]
Noel Reynolds says that the writings of Nephi can be read in part as a political tract or a "lineage history," written to document the legitimacy of Nephi's rule. [Noel Reynolds, "The Political Dimension in Nephi's Small Plates, F.A.R.M.S., p. 1]
According to John Sorenson, such histories were common among the Guatemala highland Indians when the first Spanish explorers arrived. They were used for many purposes including conferring "legitimacy and sanctity on the rulers." [John L. Sorenson, An Ancient American Setting for the Book of Mormon, F.A.R.M.S., p. 51]