The people got their king. The Lord chose Saul, a handsome Benjamite man who stood head and shoulders above the average Israeli man. His reign was more like a warlord than a proper king. He called the people to battle against the Ammonites and they won. Samuel was about to retire from his formal leadership duties, and called the nation to hear his last word of prophecy as Judge.
He started by recounting how the Lord had led them through judges, starting with the Exodus. Then he listed a few of the major wars they had with neighboring kingdoms, pointing out how Jehovah had no trouble defeating their enemies through the leadership of judges. Yet here comes one of the lesser threats, and they come insisting that God give them a king to lead them into battle.
So here you go, Israel. Behold your king! And if you obey the Lord, things will likely go well enough. But if you disobey Him, it won’t matter who wears the title, because you’ll be under some other nation’s yoke again.
Then as a reminder of just Whom they were dealing with, Samuel put on a demonstration. Here it was the wheat harvest, long after the early and latter rainy seasons. Samuel said he would call on the Lord to send a highly unseasonable thunderstorm and rain that would threaten their wheat harvest. Before the day was over, it came.
So the leadership confessed that they had sinned, and begged Samuel to intercede for them so that harvest would not be destroyed, nor would they be struck by lightening out in the open hills where they were gathered. Samuel told them they really had nothing to fear unless they forgot this lesson and chased after empty idolatry again. They must follow the Lord with all their hearts.
Of course, Samuel affirmed that he was not retiring from praying for them, only retiring from judging. But if they slipped back into idolatry, they and their king would suffer.