In this chapter, Rehoboam becomes king and all the northern tribes rebel against him.
This whole chapter exists as a response to a missing piece in Chronicles. Like I discussed in the previous chapter, Chronicles leaves out almost the entirety of 1 Kings 11, which describes Solomon committing idolatry in the later parts of his life due to the influence of his foreign wives. 1 Kings 11:11-13 explains that the LORD would take away the kingdom from Solomon because of his sins, but not during his lifetime and also leaving one tribe to his descendants for the sake of David. Because Chronicles wants to present Solomon in a more positive light, it leaves out the record of his sin and the corresponding explanation for why the kingdom is being divided during the lifetime of his son. This leaves us with the description of the rebellion against Rehoboam, but without the moralizing that we found in Kings.
This chapter is the beginning of the royal succession narrative, which continues all the way to the end of 2 Chronicles. It should be viewed in terms of the three principles that we identified in 2 Chronicles 7 when God spoke to Solomon. In case my readers have forgotten, the three themes were God's promise to forgive Israel (i.e. Judah) if they repented of their sins, to establish Solomon (and his descendants) if they walk in David's ways, and that he would destroy Judah and cast them out of the land if they worship other gods. Since the Chronicler does not want to impugn Solomon's character, we are left with God's response (tearing away the kingdom) without quite knowing the reason why. That said, verse 15 even says that Jeroboam is made king in response to a prophecy of Ahijah, which is included in 1 Kings 11:29-39, but not in Chronicles. This once again shows that the author of Chronicles, and perhaps his intended readers, were familiar with the Kings narrative even while the Chronicler is reshaping it for his own purposes. Verse 15 itself is copied from 1 Kings 12:15, but it makes a lot less sense here in Chronicles with the context of the prophecy itself removed from the text.
In any case, this chapter is definitely an instance of the second principle, because we know from elsewhere that Solomon drifted into idolatry and now the kingdom is being dis-established from his descendants as a result. A single tribe is left to him as a consequence of David's faithfulness, but most of the tribes leave. This is due to a prophecy of Ahijah, and the foolishness of Rehoboam, but even more so it's due to the justice of God punishing Solomon's idolatry. At least, that is the moral explanation for what is happening.
On the more practical side, it appears that the people are rebelling against the "heavy burden" of Solomon (v. 4). It's pretty clear this is a reference to the numerous building projects enacted by Solomon, and while the text in Chronicles clarifies that the forced laborers were all foreigners (2 Chronicles 2:17-18, 2 Chronicles 8:9-10), but from this chapter it is evident that the heavy burden has fallen on the native Israelites as well. It's clear that this is a widespread perception, and it's also clear that the people moved to challenge Rehoboam early in his reign when he would be in the weakest position to resist them. Think about it; the people were under a heavy burden during all the years of Solomon's reign, and yet we have no evidence that they ever complained to him about it, probably because it would have been suicidal. When Solomon took over as king from David, he inaugurated his reign by murdering a bunch of David's enemies, and "thus the kingdom was established in the hands of Solomon" (1 Kings 2:46). If Rehoboam had time to consolidate his rule, establish his officers and commanders throughout the country, and generally dig into the bureaucratic infrastructure of the nation, then he would be positioned to fight off any challenge and the people would lose any effective leverage to negotiate with him. This is why the people didn't complain during the reign of Solomon and why they are complaining now.
I think it's interesting that the people called for Jeroboam to come back; funny enough, 1 Kings 11:28 tells us that Solomon appointed Jeroboam over the forced labor of the house of Joseph (i.e. the northern tribes). We don't know exactly what kind of reputation Jeroboam might have had with the people, but we can reasonably speculate that he must have applied (or argued for) a lighter burden on the people because the people called for him to represent them before Rehoboam regarding the very same matter of the forced labor. Regardless of the reason why, it's clear that Jeroboam was regarded favorably by the northern tribes because afterwards they make him king.
We also see the emergence of a generational gap here. Rehoboam has two sets of advisors: the elders who advised his father Solomon and the young men who grew up with him. The elders advise him well, and the young men advise him foolishly, but Rehoboam listens to the young men instead of the elders. This was foolish, but the loss of the kingdom was unavoidable because "this turn of events was from God" (v. 15). I do think this shows the importance of listening to the wisdom of elders, especially for young people who don't have as much experience.
In verse 16, the people see that the king is not taking care of them and will only look after his own tribe, Judah, and so they cease to obey any king from the house of David.
In verse 18, we again see forced labor being the contentious issue. Rehoboam sends out Adoniram, perhaps to punish the people and perhaps expecting that the people would continue to obey the masters they were familiar with. Since the people had been performing forced labor for so long, maybe they would continue to obey out of habit. Rehoboam discovers that his ploy would not work when the people stone Adoniram to death, breaking off the last vestige of their obedience to the king.
In any case, the kingdom is divided by the hand of God and the northern tribes largely vanish from the Chronicles narrative at this point. In the next chapter, we will learn about the rest of Rehoboam's kingship.