Verse 4 is one of the places where we learn a little about the way the Lamanite world in the land of Nephi is organized. We will soon learn that King Lamoni’s father is also a king, but a king over all the land. In verse 4 we learn that Antiomno is the king in the land of Middoni. Thus, there are multiple kings over their own territory, and then an overking who governs over all of them.
This political organization differs from what we had seen in the land of Zarahemla. However, it is a known feature of the interrelationships of cities among the Maya. Each city and its land would have their ruler, their equivalent of a king, but those rulers were often beholden to another king who exercised influence over multiple cities. Thus, the Book of Mormon description of the Lamanite political situation reflects what is known of Mayan relationships. If the Book of Mormon is placed in Mesoamerica, then the fit continues to be demonstrated by the way known history appears to be reflected in the Book of Mormon text.
Although Antiomno might have been a friend to Lamoni, that doesn’t mean that there is frequent communication. Lamoni appears not to have known that Ammon’s brothers are in prison, and so he asks Ammon how it is that Ammon knew. The Lord had told him. Lamoni’s response is not to ask further questions, but to accept that the information is both correct and that it is a situation that should be corrected. Lamoni declares that he will go.
We hear about horses and chariots again. Whatever the English words represented, the animals and conveyances appear to be intended for use in official visits. We will learn that Ammon was preparing the horses and chariots for a visit to Lamoni’s father, but now we see them in the context of a visit to another king. Pictorial evidence from the Maya demonstrates that these visits were ceremonial, and did include conveyances and symbols. Connecting the two requires that we see the translation into English as representing something other than the usual connotations of those words in English, but the situations are similar.