Historical: Jacob notes that his record is necessarily incomplete. In the previous verse he confesses to incompleteness in recording his own sermons. Here he declares that he is incomplete in the historical information, much to the frustration of the modern exegete.
Jacob gives us four pieces of important historical information in these verses: population increases, wars, contentions, and multiple kings.
Population increases: When Jacob notes that his people began to be numerous, he must be speaking about a time subsequent to Nephi's death. Therefore we understand that his village is growing. If it began with around 300 households, how many more would be added?
Let's suppose that 1/3 of the households have children who mature to marrying age during the time Jacob is keeping the plates (at least a 30 year period perhaps at least 20 years by this point). The marriage pattern of the Nephites appears to be patrilocal, that is, we expect that the women go to the place of the men (this is one of the inferences from the women being sent to another village as polygamous wives).
If we presume half male and half female, and they marry each other so that there is no net gain in the number of people, we still have a probable gain of 50 households. In the Mesoamerican pattern the new household would be added into the cluster of the parents, a process that works for probably the oldest children, those who stand to inherit position. Others would be moving out of the central spaces and into the rural areas that support the center village.
This scenario does not seem sufficient to cause Jacob to remark that his people began to be numerous. Of course Jacob may simply be using a figure of speech to indicate that the people grew as a normal population would, but later figures for the Nephite polity suggest a higher growth rate. It is most likely, at the very least, that just as Nephite women were being sent to other villages, women from other villages were being brought into the village of Nephi. If for no other reason that the avoidance of incest taboos, this would appear to be necessary.
Additionally, just as I suggested that early in Lehite history a hamlet would have joined with the Lehites, it would be an understandable pattern if an emerging trading power began to attract more dependant hamlets as its wealth grew. With the description of the trading wealth and probable reasons for a trade advantage there would be sufficient incentive for other proximate villages to turn to the village of Nephi for their political and cultural center. I suggest that by the end of Jacob's life we may be conservatively looking at a village of 450 to 500 households, with perhaps some dependant hamlets. Remember that households will translate in to a greater number of adults, say slightly over two per household (father, mother, and at times and adult child prior to marriage) Therefore we are easily looking at a population over a 1,000. It would not be surprising, however, that the prosperity of the village would have attracted more people to the Nephite community, and even double that number would be reasonable.
Wars: Jacob doesn't spend time on wars, just as Nephi did not spend time on them. Nevertheless, with a village having only perhaps 40 to 50 years of existence, it would seem that warfare was a fairly frequent occurrence. Just as clearly, we must see the Nephites as ether victors or at least able to establish a draw in those conflicts. They were not conquered in the wars, or surely we would have evidence of that.
The wars also suggest that the increase in population that Jacob notes is even more difficult to sustain without an influx of outside people. Even in Mesoamerican wars that were fought more for captives than immediate killing, there would nevertheless be deaths in the battles, and what captives were taken would be just as dead to the remaining population after their removal to the capturing village or city.
For years Mesoamericanists depicted the Maya as a nation of peaceful star-gazing, priests. Recent work underlines the continuous nature of Maya warfare. While the data come from a period later than the Book of Mormon, those data are nevertheless coming from an area that drank deeply from their cultural roots in the same area as that proposed for the Book of Mormon. With the evidence of such constant warfare in the Book of Mormon, warfare that begins very early in the life of the Nephite people, it appears that even at this early time this part of the world existed in a constant state of anticipation or participation in warfare.
However, there is an interesting suggestion that wars might actually have benefited the people of Nephi. In discussing the effects of a series of wars between two major Maya polities, Schele and Matthews suggest:
" One result of the competition for territory, resources, and tribute was a cataclysmic series of wars between the competing alliances led by Tikal and Kalak'mul that began in the sixth century. In the archaeology, kingdoms that won wars during these conflicts show enormous growth in population, in wealth at all social levels, in access to foreign goods, and in extensive building programs. Losers usually show the reverse, but being a winner or loser was rarely permanent. Reversals of fortunes and the resulting change in economic status were commonplace. (Schele, Linda, and Peter Matthews. The Code of Kings. Scribner. 1998, p.20).
If this later pattern were to be imputed forward in time, the victory in wars would have increased the prestige of the Nephites, and brought with it an increase in wealth through tribute as well as trade. Note that the wealth through tribute occurs at all social levels, so that in and of itself is no explanation for the social divisions among the Nephites. The last piece of information is that the attached peoples also become more numerous. It is possible that the victories in wars expanded the population significantly beyond the number of households I was suggesting. The dampening data on population for this time period is archaeological. Even though the "Nephis" might be called "kings" it is doubtful that there was a much of a state at this time period, and certainly none is known archaeologically. Joyce Marcus suggest that populations around 1000-2000 people (with about 5 people per household, making the 400 household level a very large community in this time period) were perhaps the largest sizes that could be sustained prior to the development of the state (Marcus, Joyce. "The Size of the Early Mesoamerican Village." In: The Early Mesoamerican Village. ed. Kent V. Flannery. Academic Press, 1976, p. 89).
Contentions: Why does Jacob note both war and contentions? We might be tempted to lump them into the same category, but I suspect that Jacob is telling us more than two words for the same thing. Wars are external affairs. I suggest that contentions are internal affairs, divisions of opinion, culture, or politics that provided occasions of discord in the community. The very fact that this summary comes on the heels of a community discord strengthens this position. We may understand the forces leading to such internal contentions better if we picture this incipient Nephite nation as a conglomerate people, built on the basis of a small core of Old World people with desirable talents, and the influx of large numbers of "others" who would bring with them very different cultural (and religious) expectations. The presence of these competing ideas is the kindling for social contentions.
Multiple kings: The last piece of information is Jacob's restatement that he has seen multiple kings. As suggested earlier this too is probably an artifact of a society engaged in Mesoamerican warfare. Schele and Freidel note: " There were many hazards o challenge kings - wars, intrigues, and natural catastrophes. A king was literally at risk all his life; and more than one king ended his rule, not by dying of peaceful old age but by being taken captive in a war he was too old to fight. (Schele, Linda, and David Freidel. A Forest of Kings. New York, William Morrow and Company, Inc. 1990, p. 60).