In the greater land of Zarahemla there was no support for Amlici's kingship. Nevertheless, there continued to be support for him, in some locations. The solution was secession.
Amlici's people "gathered themselves together." This would require a removal from other locations and a relocation to a new community. Within that community Amilci would both have the "voice of the people" necessary to rule, but he would have a location where he could rule and be obeyed. The Amlicite scenario doesn't work unless they become a separate community.
This separation from the people of Zarahemla both indicates the reason that Amlici could function as a king over a people as well as the reason why they initiated military action against the Zarahemlaites. As a people removed from the land of Zarahemla, they were also removed from the economic power base of Zarahemla.
As a people with fewer resources due to the lesser population (the majority having rejected Amlici's kinship) they would be envious of the greater material wealth of the more established community. Since the amassing of the trappings of wealth was one of the concomitant aspects of Mesoamerican kingship, it is virtually certain that the was a desire for this economic prosperity in addition to the fact of the king himself. In the Mesoamerican tradition, the increase in wealth came through trade or conquest. Clearly, the Amlicites chose conquest.
Geography: When the Amlicites removed themselves from the land of Zarahemla, where did they go? Sorenson suggests:
"But where was home to the rebels, where they "gathered" and whence they "came"? While we are not told, we can infer the location. They would not have come from upriver, of course. Had that been their location, they would simply have joined with the Lamanite force as it came through their territory. Nothing said at any point in the Nephite record suggests sizable populations away from the river zone on either its eastward or westward sides. But there was room downstream. The downriver stretch is rarely mentioned in the Book of Mormon. It was once, during the later attack led by one Coriantumr. Then the Lamanites seized Zarahemla without warning and pushed on downriver through "the most capital parts of the land" (Helaman 1:27).
The geography we are following makes that area coincide with the lower central depression of Chiapas, where the speakers of the Zoquean language had long lived. They had been in the land long before the Nephites arrived. Their ancestors had been bearers of the Olmec culture in the time of the Jaredites. There is little reason to question that they were of basically the same stock as the folk followers of chief Zarahemla.
Their leaders would have lost a great deal of power and privilege when the Nephite intruders took over rulership in Mosiah I's day. At the time we are now considering, the expansion of the Nephite elite's power throughout the entire valley could well have spurred this "nobility" to wish to regain rulership for one of their own lineages. This is the logical base from which an Amlici probably proceeded. The variety of peoples under Nephite domination was so geographically divided by river and "wilderness" areas and so linguistically and culturally varied that "dissension" and power struggles among the localized groups, like the one started by Amlici, long continued to challenge the "Nephis," the ruling line descended from the original king, Nephi.
Evidence from Chiapas suggests that the Santa Rosa/Zarahemla area might be at loggerheads with the area downstream. The Chiapa de Corzo site, the largest city within the entire central depression at this time and the heart of that downstream sector, was larger and more prosperous than Santa Rosa. No wonder it might rebel against overlordship located upstream.
Furthermore, at this period of time (the second century B.C.) Chiapa de Corzo maintained clear-cut cultural ties to the Mayan speakers to the south, that is, to Lamanite country in our Book of Mormon terms. An alliance between Amlicites based in the Chiapa de Corzo area and the Lamanites in Nephi (highland Guatemala) would have formed a vise, putting pressure on the Nephite center. Of course, we cannot say for sure that this geographical arrangement is how things really were. No one knows enough facts yet to be sure, but it very reasonably could have been so." (Sorenson, John L. An Ancient American Setting for the Book of Mormon. FARMS 1985, p. 196-7).